Official SAT II Mathematics IC/IIC Discussion Topic





Click here to go to the NEW College Discussion Forum

Discus: SAT/ACT Tests and Test Preparation: May 2004 Archive: Official SAT II Mathematics IC/IIC Discussion Topic
By Ihatesats (Ihatesats) on Saturday, May 01, 2004 - 02:13 am: Edit

Gearing up.

By Y17k (Y17k) on Saturday, May 01, 2004 - 03:21 am: Edit

i took it about 6 hours ago... not so hard...
whats the curve usually like (i.e. how many can u get wrong and still get a 800?)

By Jszab (Jszab) on Saturday, May 01, 2004 - 09:14 am: Edit

In my 2000's reals, You can have 5 errors.

By Varr (Varr) on Saturday, May 01, 2004 - 09:51 am: Edit

which book would/did you guys use/used for the SATII MATHIIC?????

Thanks,
Varenka

By Doerame (Doerame) on Saturday, May 01, 2004 - 10:26 am: Edit

we can't post until tomorrow (may 2)??

varr: i used sparknotes

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 11:14 am: Edit

now why in the world would you make a thread that will cover IC and IIC?

that just asks for confusion

By Obiwan (Obiwan) on Saturday, May 01, 2004 - 11:16 am: Edit

You can post after noon EDT today. Warning notice had the wrong date.

--Moderator Obiwan

By Blane1086 (Blane1086) on Saturday, May 01, 2004 - 12:00 pm: Edit

Hey Varr, use the Spark Notes 5 additional tests. I left two blank today and got one wrong that I know of, but many people in my class left 10+ blank. The tests in the Spark Notes books are pretty indicative of what will be on the IIC and US History SAT II's (both of which I just took).

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:12 pm: Edit

What did yall get for the last one on 2C? I left it blank. It was the one sin(theta) = Xsquared. What does sin(2theta) equal?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 12:12 pm: Edit

it's noon. i thought Math IIC was fairly easy. I've never seen any practice tests, so I don't know how it was compared to older ones.

I answered all and i'm pretty sure I missed two.. hopefully that'll be it.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 12:14 pm: Edit

for the last i got

2(x^2)(sqrt(1-x^4))

whatd you guys for the probbility of the white car one and the intersection of three planes?

By Quack87 (Quack87) on Saturday, May 01, 2004 - 12:14 pm: Edit

i skipped a bunch (6 or 7 maybe). in the kaplan book, you can skip 8 and get an 800. does anyone remember the one about 3 planes intersecting? the question was something like, can they create a point, plane, or something.

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:15 pm: Edit

15% for the white car one = 3/20

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:16 pm: Edit

The question was can they intersect to make a line, ray, or point. I think it was point and line.

By Quack87 (Quack87) on Saturday, May 01, 2004 - 12:17 pm: Edit

for the probability thing i got something like 25. i put in 4 nCr 2 + 4 nCr 3 (or w/e the numbers were).

By Suzygirl (Suzygirl) on Saturday, May 01, 2004 - 12:21 pm: Edit

i think the planes one is ray and line.... three planes can't intersect at a point can they?
does anyone know how many you can miss or leave blank to stay in the 700's ?

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:22 pm: Edit

The number of choices of three or four person groups selected out of five people was 25.

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:23 pm: Edit

They can intersect at a point. Think of the xzy axes.

By Blane1086 (Blane1086) on Saturday, May 01, 2004 - 12:34 pm: Edit

For the plane one, I put a point and a line. Think of the point like the top of a pyramid. How did you get 25 for 5 nCr 3 + 5 nCr 4?

By Cherrybarry (Cherrybarry) on Saturday, May 01, 2004 - 12:43 pm: Edit

what did you guys get for the equivalent one? where f(x)=f(-x). It didn't seem like any of them worked. None of them were even functions. I hope it was a typo. Yeah right.

By Jszab (Jszab) on Saturday, May 01, 2004 - 12:43 pm: Edit

Qwert271 Can You draw when the planes are intersecting in one point?

By Upandcomer22 (Upandcomer22) on Saturday, May 01, 2004 - 12:45 pm: Edit

What did u get for the f(x)=(x,y,0) question?

I put (0,0,0)

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 12:45 pm: Edit

i think the equiv function was the one where there was no constant term and the degree of every term was odd.. that way you can divide by -1 and get the same equation, making it equiv

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:47 pm: Edit

The xyz axis. The point (0,0,0) (x,y,z) is where they all intersect, at only one point. I cant draw it here!

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 12:48 pm: Edit

0,z,0

By Smadans (Smadans) on Saturday, May 01, 2004 - 12:49 pm: Edit

the one about the group of 4 or 3 out of five people is 15 cuz (5 nCr 4) + (5 nCr 3) = 15

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 12:49 pm: Edit

yeah it was the one: X(raised to 5) + 3Xcubed - X =0. If you substitute in -x you get -X(raised to the 5) - 3Xcubed + X = 0 which is equivalent to the original.

By Pinacolada (Pinacolada) on Saturday, May 01, 2004 - 12:51 pm: Edit

hmm i can't visualize the point..i thought it could only be a line
5 nCr 3 + 5 nCr 4 = 15 doesn't it?

By Upandcomer22 (Upandcomer22) on Saturday, May 01, 2004 - 12:51 pm: Edit

for the last one i put 2x^2, it was choice A. The question was sin(t)=x^2 something something something

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 12:54 pm: Edit

sin t = x^2
sin 2t = 2(sin t)(cos t)
2x^2 cos t
the identity 1 = sin^2 + cos ^2 gives

cos t = sqrt ( 1- (sin t)^2)

so 2x^2 sqrt (1-x^4)

By Cherrybarry (Cherrybarry) on Saturday, May 01, 2004 - 12:56 pm: Edit

For the last one, I put 2x^2sqr(1-x^4) since cos(q)=sqr(1-(sin q)^2)=sqr(1-x^4)

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:13 pm: Edit

xyz axes is two planes...The answer is ONLY a line, and remember that planes are infinite, so you can't make a pyramid...jeez.

And the group one was 15, 5c3 + 5c4 = 20/2 + 5/1

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:17 pm: Edit

Also, the answer to the f(x,y,z) is definitely (0,z,0)

And the f(x)=f(-x) has to be an even function, if it has odd degrees it gets warped.

The answer choice was A, x^6-x^5+3 -- because both solution sets are imaginary (no solutions).

All the other ones have differnet solutions (you can verify by your calculator).

You are wrong, if you divide everything by -1 you still get a different equation.

Peace!

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:19 pm: Edit

Also for people saying xyz, is three planes, think about the just the xy plane, it is ONE PLANE, thats why its called the XY PLANE, therefore adding the third dimension creates only two planes at any given point.

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 01:24 pm: Edit

xy, yz, and xz planes.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:25 pm: Edit

um.. thats not an even function. and yes, if you divide by -1, you do get the same function

By Mysticaura (Mysticaura) on Saturday, May 01, 2004 - 01:27 pm: Edit

what was the asnwer to the plane flying at 8 kilometers and the distance btwn 2 cities?? i put li,ke 4.9 or something

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:28 pm: Edit

there was no even function in any of the choices.

x^5 + x^3 - x = 0

sub in -x

-x^5 - x^3 + x = 0
divide by -1
voila
x^5 + x^3 - x = 0

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:31 pm: Edit

Qwert you're wrong, there is no way three planes can intersect at a point, and the xyz coordinate system does not have three planes intersecting at one point, the xy plane is a piece of paper, with a cross through it, the z plane is perpendicular to that paper, TWO PLANES.

By Pinacolada (Pinacolada) on Saturday, May 01, 2004 - 01:33 pm: Edit

for equivalent equations only the solutions have to be the same. amitoman is right. the one with all odd exponents would be flipped over the x-axis with the same zeros.

By Cherrybarry (Cherrybarry) on Saturday, May 01, 2004 - 01:34 pm: Edit

Yeah, that was an odd function where f(x)=-f(-x).

The problem stated equivalence was when x and -x give the same y values, or was it that they give the same range? I hope it wasn't the latter. lol

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:34 pm: Edit

if you equations of three lines.. example:
x + y + z = 4
x - 2y - z = 1
2x - y - 2z = -1

and you solve the system to get: (2,-1,3)

is that not where the planes intersect?

(by the way, i put line only also.. but i think we're wrong)

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:35 pm: Edit

Excuse me, I didn't mean even function but I'd like you to graph both of those equations WITHOUT dividing by -1, and you get two completely graphs, I'm pretty sure you can't just divide by two, thats like having.

2x^4+2x^2 and dividing by two, you get a different function when you do that.

SO THERE
HA.

Also graph x^6+x^5+3, and graph x^6-x^5+3 and you'll realize that both their solution sets are the same (no real solutions)

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:37 pm: Edit

THREE LINES ARE NOT THREE PLANES AMITAN.-Planes are flat surfaces that spread INFINITELY.

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:38 pm: Edit

Go to AIM CHAT "MATH2C" To discuss the test.

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 01:39 pm: Edit

God! think of a 3D graphing calculator window that is [-10, 10] [-10,10] [-10, 10]. Now, there are eight quadrants, each bounded by THREE perpendicular sides: xy, yz, xz.

On the xy plane, there are four quadrants, each bounded by two lines. When you introduce the z they become planes, teh xy axis is projected 3dimensionally forward and backward.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:40 pm: Edit

so you're saying:

x^2 = -2 and x^2 = -4 are equivalent because they both dont have any real solutions? thats not what defines solution set.

and yes, if an equation is equated to 0, you can divide by -1

-x+3 = 0 is the same as x-3 = 0

your definiton of solution set is skewed. it's not what TYPE of solution set there is.. that they just have the same roots

from their given defintion, the equations

x^2 - 6x + 8 = 0 is equivalent
2x^2 - 12x^2 + 16 =0

they aren't the same graph

but they both yield the same solution set
{4,2}

the graphs dont have to be the same

By Mysticaura (Mysticaura) on Saturday, May 01, 2004 - 01:42 pm: Edit

So guys what was the answer to the plane flying at 8 kilometers ?!?!??!?!?! Anyone KNow??? It was like 2 triangles with angles of depressions

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:43 pm: Edit

take that back what i said about

-x + 3 is the same as x-3

i meant they have same solutions

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 01:43 pm: Edit

sorry, i remember the problem.. but i really can't remember what i got. 4.9 sounds familiar, actually.. but i'm not entirely sure.

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 01:47 pm: Edit

ok I figured it out, your answer works but mine works as well because their solution sets are both NO REAL SOLUTIOns, therefore it is an error in the problem and I have emailed the collegeboard.

By Sraj87 (Sraj87) on Saturday, May 01, 2004 - 01:56 pm: Edit

This was probably an easy question... but what was the answer to the one about the frequency of the equation like y=4 sin (2x-1)? I got 2/pi but that wasn't even one of the answers, so does anyone know it?

Overall, i thought this was a whole lot easier than the barron's iic book, which made this seem a whole lot harder than the actual IIC was.

By Quack87 (Quack87) on Saturday, May 01, 2004 - 02:00 pm: Edit

sraj- i got 1/2pi for the frequency...i think...

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:02 pm: Edit

1 / pi?

it was 4sin (2x-1)

the period is 2pi / 2

so frequence is 1 /pi

By Commonsense (Commonsense) on Saturday, May 01, 2004 - 02:06 pm: Edit

i got 1/pi too

i graphed it and found the period

By Paradox (Paradox) on Saturday, May 01, 2004 - 02:08 pm: Edit

The period of the standard sine function is 2*pi. Since amplitude and shifts don't matter, y=4sin(2x-1) ~ y=sin(2x). This halves the period and therefore doubles the frequency to 1/pi.

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:08 pm: Edit

second to last question:

7/8 <= x <= 4/3
What is the Probability of choosing a number greater than 1?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:10 pm: Edit

the distance between the two is 11/24

4/3 - 1 = 1/3

(1/3)/(11/24) = 8/11

By Quack87 (Quack87) on Saturday, May 01, 2004 - 02:11 pm: Edit

1/3? but it sounds too easy.

By Sraj87 (Sraj87) on Saturday, May 01, 2004 - 02:14 pm: Edit

I got 3/4 because

Easiest way is to make it into a common denominator, although this may be the wrong way to do it and I could be wrong:

7/8 = 21/24, 4/3= 32/24

21/24, 22/24, 23/24 = less than 1
24 through 32 / 24 = greater than or equal to

That leaves 9 of 12 as greater than or equal to, although this screwed up way of getting it makes me think that I could be wrong.

By Micky (Micky) on Saturday, May 01, 2004 - 02:18 pm: Edit

which section was the experimental if you have four verbal

section 1 - math
2- verbal
3- math
4- verbal
5- verbal
6- math
7- verbal
dickens, perfume, little girl w/ family, or 15 min topic?
is the 15 min ever experimental?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:18 pm: Edit

the problem didnt say "find the probabibilty that the INTEGER is greater than 1"

it said "number".. it can be anything from 1 to 1.25 to .8888.

you can't count the choices in this case..

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:18 pm: Edit

micky, this is SAT II talk..

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:19 pm: Edit

i agree w/ amitoman... 8/11

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:29 pm: Edit

let's keep this going guys... does anyone remember the other I,II,III choice question... i remember that i put "III only" but i dont remember the question... i think it had something to do w/ inequalities

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:30 pm: Edit

Yeah, it gave equations of three graphs...don't remember what it was asking though. But I did get III only.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:32 pm: Edit

oh ya..

which of them have a range of positive numbers only i think was the question.

and yes i got III as well

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:33 pm: Edit

How about the question that asked for the maximum of the product of some function of sin(x) and cos(x)?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:34 pm: Edit

11.8

you can graph the product, and use the trace function on the calculator to find the peak

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:35 pm: Edit

does anyone remember the answers to the questions about sequences... there was one about geometric sequences for which i got 6

and then there was another question about sequences in general.... it gave "An = (An-1 + 1)/(An-2)" or something along those lines...
it gave A1 and A2 i think and asked us to find A4

does anyone remember answers for these?

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:36 pm: Edit

Yeah, I got 11.8 as well. I also got 6 for the geometric sequence. Can't remember what I got for the An = (An-1 + 1)/(An-2) one, however.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:37 pm: Edit

was it 2.57 or something? i'm trying to do the problem again from what i remember, but i don't know if i remember the numbers correctly

and ya.. 6 for the geo series

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:38 pm: Edit

that formula is most likely incorrect by the way... i was just going from memory

i think, i'm not sure but i think the answer that i put was 9... 9 sticks out in my head for some reason

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:39 pm: Edit

i remember 9 too.. but i don't think that was the final answer. i don't know for sure

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:40 pm: Edit

Wasn't there a question that asked something like "which of the following intervals makes this function (can't remember the function) > 0"? Anyone remember?

Pretty sure I got every question right. Finished like 30 minutes early and did the whole thing again (thanks, Barrons).

All-in-all, I thought it was ridiculously easy. Anyone else think this?

By Tired_Student (Tired_Student) on Saturday, May 01, 2004 - 02:41 pm: Edit

Im taking the IIC test in October, and I have the barrons IIC and arco IIC. What other books would you guys recommend that is most similar to the styles and types of questions that appear on this test?

I was really messed up for the Writing test because the barrons book is nothing like the real test

My friend was pretty messed up too for the IC because Barrons stressed things that didnt show up at all on the IC test. BAH BARRONS

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:41 pm: Edit

yes.. tahts the one where the answer was III only

i thought it was very easy, but i cant compare it to older tests.

i'm expecting an 800, but silly mistakes will be what determine it

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:42 pm: Edit

for the interval question... i put 3 < x < 4 i think... i graphed it so it was easy

and 9 may have been equal to A3 ...

By Doerame (Doerame) on Saturday, May 01, 2004 - 02:42 pm: Edit

sparknotes is really good... i'm hoping for an 800 too... i'm looking at 2 wrong and 2 omitted right now

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:43 pm: Edit

i didn't use a book, but i would suggest you get Real SAT IIs.. those are always more realistic.. and along with that a barrons or princeton book is always helpful is sharping up skills you may feel shady on.

By Paradox (Paradox) on Saturday, May 01, 2004 - 02:43 pm: Edit

The question was: A[1]=0.5, A[2]=3.5, A[n]=(A[n-1]+1)/A[n-2]. What is A[4]?
A[3]=9, and then A[4]=20/7 ~ 2.85.

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:44 pm: Edit

If you work through the Barrons IIC, and understand it, the actual SAT II test will seem like an absolute breeze.

Or at least that's what I think. (Also, Sparknotes Online offers practice SAT II exams for a very cheap cost - something like 25 bucks for 3-5 exams of several different subjects - that are quite similar to the actual thing).

By Silmon77 (Silmon77) on Saturday, May 01, 2004 - 02:44 pm: Edit

I skipped 6 (ran out of time on the last 3) and missed at least 2. Can I still get a 800?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 02:44 pm: Edit

oh oops.. actually, for that interval one i got -1 < x < -2 if i remember correctly. i don't even think 3 < x < 4 was a choice, although it did work

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 02:47 pm: Edit

Yeah, I agree with Amitoman. Both -2<x<-1 and 3<x<4 were possible solutions, but since 3<x<4 wasn't a choice, the answer was -2<x<-1.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 03:12 pm: Edit

Silmon, if what you said is the case, you probably got 750+.. maybe 780

or who knows.. the curve could get you an 800

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 03:17 pm: Edit

How about the question about the woman getting a salary of, like, 300 bucks?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 03:20 pm: Edit

1667?

By Qwert271 (Qwert271) on Saturday, May 01, 2004 - 03:25 pm: Edit

thats what I got. the one that asked for a curve of 'k - f(x)' when they showed you what f(x) looked like. it was flipped upside down and shifted up, right?

Also, waht did you get for the one with the remained of 452 divided by prime number n. I got zero for the remainder when 50 is divided by n.

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 03:27 pm: Edit

Yep. Or at least that's what I put.

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 03:28 pm: Edit

Sorry. Double post.

By Kevinkleinz (Kevinkleinz) on Saturday, May 01, 2004 - 03:32 pm: Edit

The prime number was 29, because 452/29 = 15.something, 15*29 = 435, and 452 - 435 = 17. Thus, the remainder when 50 is divided by 29 is 50-29 or 21.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 03:35 pm: Edit

for the graph one, yes.. flipped and shifted up

as for the remainder one: 21

it had a remainder of 17 when divided by n
so (452 - 17) is divisible by n

452-17=435, which factors into 3*5*29
you cant have a remainder of 17 if you're dividing something by 3 and 5, so n is 29
50/29 has remainder of 21.

By Theli0nheart (Theli0nheart) on Saturday, May 01, 2004 - 04:23 pm: Edit

The plane one was 5.28, you had to use supplementary angles and then use law of sines to find the distance.

By Kingroger317 (Kingroger317) on Saturday, May 01, 2004 - 04:25 pm: Edit

what were the #48

with the f(5) - f(25)

and what was the
one after that #49 with probability of 7/8 <X < 4/3 or something like that.. PLEASE

By Theli0nheart (Theli0nheart) on Saturday, May 01, 2004 - 04:31 pm: Edit

#48 was -k, I'm pretty sure

klog[5]5-klog[5]25=
k(1)-k(2)=
-k

#49 was 8/11, if I can remember

By Cliff (Cliff) on Saturday, May 01, 2004 - 04:32 pm: Edit

Did anyone here take Math IC and want to discuss it?

By Kingroger317 (Kingroger317) on Saturday, May 01, 2004 - 04:34 pm: Edit

also what was the one wit hthe 8 meter plane distance????

also how many people with the groups of 4 and 3??? thxs!!

can u IM me : Roger9917 SN

By Tlz (Tlz) on Saturday, May 01, 2004 - 04:37 pm: Edit

Post removed.
Moderator

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 04:43 pm: Edit

for the 8 meter plane, some say 4.9, other guys says 5.28... i can't remember exactly what i put.

groups of 4,3 is 15. 5C4 + 5C3

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 04:44 pm: Edit

tlz, looks like your thread got deleted

By Kingroger317 (Kingroger317) on Saturday, May 01, 2004 - 04:48 pm: Edit

intersection between 3 planes is??
line, ray, point?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 04:50 pm: Edit

theres tons of debate between the question

some say point and line

others say only line

i don't know

By Theli0nheart (Theli0nheart) on Saturday, May 01, 2004 - 04:57 pm: Edit

The answer is a point and a line.

Here's my explanation: plane x and plane y intersect to form a line. Let plane z be the variable plane, and let it intersect (at all points) with the intersection xy. So there, you have your line.

Now, go back to the intersection between x and y. Instead of letting plane z intersect at all points with the line, let it intersect at only one point. Voila, your point.

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 05:07 pm: Edit

the answer to the plane problem is 5.8. i just did it again

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 05:09 pm: Edit

so what do you guys think the curve for an 800 will be?

By Stfate1 (Stfate1) on Saturday, May 01, 2004 - 05:25 pm: Edit

I am sure the airplane one was the largest of the choices, 5.28 i think. You had to figure out about 3 angle measures using properties of triangles and then use the Law of sines to get the final answer.

Does anyone know:

Q: ax = a +2x
What can a not equal?

Q: The one with the $300 salary. I got 1667.

Q: The one that gave you the formula 55 + (2(t-1)) and someone worked for 2.75 hours. I just plugged in 2.75 for t. was that right?

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 05:27 pm: Edit

for the first one, a can't be 2
ax - 2x = a
x (a - 2) = a
x = a/(a-2), for which 2 is undefined

or better yet, if a = 2, then 0 = a, contradiction

i got 1667 too, so dd many others

yes, i'm almost positive you just plug in 2.75

By Thunder7 (Thunder7) on Saturday, May 01, 2004 - 05:33 pm: Edit

Removed.
Moderator

By Scion (Scion) on Saturday, May 01, 2004 - 05:55 pm: Edit

can someone teach me bout logs? i learned it in alg 2 w/ trig, but i just cant seem to get it anymore now. thanks

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 05:57 pm: Edit

log_a b = c says a^c = b

log_a b = log b / log a

log (ab) = log a + log b
log (a/b) = log a - log b

alog b = log (b^a)

those are the basics

By Mysticaura (Mysticaura) on Saturday, May 01, 2004 - 06:09 pm: Edit

anyone remember the f(fx) wher eit gave u a table and what not...I was real confused on that one...

By Amitoman (Amitoman) on Saturday, May 01, 2004 - 06:12 pm: Edit

2

By Doerame (Doerame) on Saturday, May 01, 2004 - 09:59 pm: Edit

by any chance does anyone remember what number the question with these choices was:
A, x^6-x^5+3
x^5 + x^3 - x = 0

etc... was it 43 by any chance?

By Dannyferizzle (Dannyferizzle) on Saturday, May 01, 2004 - 11:19 pm: Edit

"Now, go back to the intersection between x and y. Instead of letting plane z intersect at all points with the line, let it intersect at only one point. Voila, your point. "

It's pretty easy to say they intersect in a point by just saying "Intersect at only one point" -- Can you be a little more descripitive? Remember that planes go infinitely in all two dimensinal directions, the answer is line only-

By Gameguy56 (Gameguy56) on Saturday, May 01, 2004 - 11:28 pm: Edit

http://www.josechu.com/planes_in_3d/

boom, right there

3 planes can intersect to 1 point, a line, but NOT a ray

By Cherrybarry (Cherrybarry) on Sunday, May 02, 2004 - 01:19 am: Edit

just look at the corner of your room

By Kousuke (Kousuke) on Sunday, May 02, 2004 - 01:49 am: Edit

what about the obtuse triangle with angle measurements of something like 38 and 41 or something, and base length 17(?) ? i didnt get that one at all, all of the others seemed to be fairly easy, but this one i didnt get along with the point/ray/line one. is a raw score of 47~48 still 800?

By Commonsense (Commonsense) on Sunday, May 02, 2004 - 02:47 am: Edit

47-48 is definitely 800

By Dannyferizzle (Dannyferizzle) on Sunday, May 02, 2004 - 10:37 am: Edit

Does anyone agree with me that the one with x^6+x^5+3 and
x^3+x+3 or something like that are both possible answers (people already say that the 2nd one is definite possibility) but x^6+x^5 both have hte same solution set (NO REALS) -- When you alter x to be -x,

They are both curves above the x-axis, also Math IIC says at the beginning that assume all the things are real unless otherwise stated, so the answer must be both of them, people who answered those two should get credit.

By Lahlahlah (Lahlahlah) on Sunday, May 02, 2004 - 10:48 am: Edit

Omfg, 3 planes do intersect in one point youd

think about the x y and z axis, they intersect at the origin ....

By Mysticaura (Mysticaura) on Sunday, May 02, 2004 - 11:30 am: Edit

someone tell collegeboard about the X^6+x^5+3 problem...it should be taken out

By Amitoman (Amitoman) on Sunday, May 02, 2004 - 11:50 am: Edit

it's not going to be taken out.. try if you want. it was a legitimate question

By Kevinkleinz (Kevinkleinz) on Sunday, May 02, 2004 - 11:59 am: Edit

Yeah, I doubt it's going to be taken out...

And, I'm just curious...why are you absolutely positive that your particular answer contained no real solutions?

By Paradox (Paradox) on Sunday, May 02, 2004 - 12:03 pm: Edit

For some reason, this hasn't been made clear.
If you have a[0]+a[1]*x+...+a[n]*x^n=0, the only polynomials that have the same solution set are those that are some nonzero factor k times the original one, i.e. k*a[0]+k*a[i]*x+...+k*a[n]*x^n=0.
In this problem, this means that substituting -x for x has to change every term in exactly the same way -- either by keeping it the same, or by multiplying it by -1. This can be accomplished either by having all even powers of x in the polynomial (giving the same equation) or all odd powers (giving the negative). Since there was exactly one choice that satisfied this constraint, it was a perfectly valid question.

By Kevinkleinz (Kevinkleinz) on Sunday, May 02, 2004 - 12:07 pm: Edit

Oh no, I completely agree with you, Paradox; it was definately the answer that switched the signs when you plugged in -x (I also graphed the two functions on my calc simultaneously just to make sure :-)

By Kevinkleinz (Kevinkleinz) on Sunday, May 02, 2004 - 12:23 pm: Edit

Amitoman- you said you thought that you missed two? Which ones?

By Amitoman (Amitoman) on Sunday, May 02, 2004 - 12:36 pm: Edit

i missed the intersection of planes one definitely.. and i'm afraid i did the flying plane one wrong, because 4.9 sounds strikingly similar.. but i'm not positive.

hopefully that'll be it.

By Jlaws30 (Jlaws30) on Sunday, May 02, 2004 - 01:20 pm: Edit

I skipped four and I think I got two wrong. This is my first time taking the test so I don't really know what kind of curve to expect. What score do you think I will get?

By Amitoman (Amitoman) on Sunday, May 02, 2004 - 01:34 pm: Edit

that would leave you at a raw score of 43.5, which leaves you at a pretty good chance of an 800.. gotta love the math iic curve

By Dannyferizzle (Dannyferizzle) on Sunday, May 02, 2004 - 02:00 pm: Edit

OK THREE PLANES CAN INTERSECT IN ONE POINT BUT THE XYZ AXES IS NOT AN EXMAPLE OF THE THREE PLANES INTERSECTING, THAT IS TWO PLANES, the Z PLANE and the XY PLANE.

Furthermore, AMitoman, I emailed the collegeboard and I'm pretty sure that both answers will count--it wont be taken out but both answers will count,

And HOw am I so sure about it being no solutions? I graphed the equations like thirty times and they are both way above the x-axis, guarnateeing NO REAL SOLUTIONS.

By Amitoman (Amitoman) on Sunday, May 02, 2004 - 02:04 pm: Edit

actually.. the xyz coordinate system can be thought of intersecting in a point.

XY plane
YZ plane
ZX plane

By Jlaws30 (Jlaws30) on Sunday, May 02, 2004 - 02:07 pm: Edit

By Jlaws30 (Jlaws30) on Sunday, May 02, 2004 - 03:46 pm: Edit

So was this math IIC test easier than usual?

By Kevinkleinz (Kevinkleinz) on Sunday, May 02, 2004 - 03:52 pm: Edit

I really can't compare it to past tests, as this was the first time I've taken it. I will say, however, that I finished 30 minutes early, did the whole thing twice (and some problems three or four times), thought that it was borderline commonsense compared to Barrons and relatively easy compared to Sparknotes.

By Gameguy56 (Gameguy56) on Sunday, May 02, 2004 - 05:28 pm: Edit

yea, this IIC seemed a TON easier than the sparknotes tests. (no questions about demorgan's laws, no obscure trig identities, etc). I omitted none and I think 5-6 wrong. I think possibly a 800, but most likely I'll get 760-780

By Dannyferizzle (Dannyferizzle) on Monday, May 03, 2004 - 11:06 am: Edit

ZY and ZX are not planes--ok draw out your XY coordinate system on a piece of paper, thats ONE PLANE, XY right there ONE PLANE, the X and Y coordinates all on one planes, then the z plane is just another piece of paper perpendicular to that page.

ugh.

By Kevinkleinz (Kevinkleinz) on Monday, May 03, 2004 - 12:45 pm: Edit

Um, yes, they are. As someone said earlier, look at the corner of your room.

By Amitoman (Amitoman) on Monday, May 03, 2004 - 03:11 pm: Edit

dude danny... you don't know what you're talking about.

give it up, you got one wrong

By Apocalypse_Now (Apocalypse_Now) on Monday, May 03, 2004 - 06:30 pm: Edit

Danny, i'm sorry but you are completely wrong. Even your analogy about the piece of paper is incomplete. There are TWO planes perpendicular to the xy plane. One that intersects the xy plane along the y-axis and one that intersects the xy plane along the x-axis.

By Gneugen (Gneugen) on Monday, May 03, 2004 - 07:46 pm: Edit

Danny, the plane that you see on a piece of paper is where the y plane intersects the x plane. The paper represents the y plane, and the x-axis represents of course, where the x plane is intersecting the y plane. When you put your other piece of paper, the z plane, perpendicular to the initial plane, you now have a method of seeing where the x and y plane intersect, in 3d space. Since the planes are all perpendicular to one another, there is only one place where all the planes coexist. To properly make a paper-plane (hah hah) analogy, you'd need two pieces of paper for the x and y planes, and yet a third piece of paper for the z plane.

By Kevinkleinz (Kevinkleinz) on Monday, May 03, 2004 - 07:57 pm: Edit

Anyone else think they got a perfect raw score?

Just curious.


Report an offensive message on this page    E-mail this page to a friend
Posting is currently disabled in this topic. Contact your discussion moderator for more information.

Administrator's Control Panel -- Board Moderators Only
Administer Page