CALC question, proving stuff?!

Discus: SAT/ACT Tests and Test Preparation: October 2003 Archive: CALC question, proving stuff?!
 By Entropie (Entropie) on Wednesday, October 08, 2003 - 11:29 pm: Edit

ok my teacher gave us this question:

Prove the following- if f is continuous on the closed interval [a , b] and k is any number between f (a) and f (b), then there is at least one number c in [a , b] such that f (c) = k.

i just looked at it and i was like "wtf?". Im completely lost, in fact, i dont even know how to begin. please help

 By Entropie (Entropie) on Wednesday, October 08, 2003 - 11:33 pm: Edit

actually i know what it means, it's a simple concept...now proving it, i dont know how to do that. How can he expect us to prove it without learning how to prove crap like this?!

it must be so simple that he doesnt need to teach us, but it's going over my head.

 By Tanman (Tanman) on Wednesday, October 08, 2003 - 11:45 pm: Edit

Isn't this the intermediate value theorem? Here's a site I found online: http://www.wikipedia.org/wiki/Intermediate_value_theorem It's a bit hard to understand so you might want to try googling "prove intermediate value theorem" for more help

 By Entropie (Entropie) on Thursday, October 09, 2003 - 02:26 am: Edit

wtf this thing is impossible to prove... ive called 5 people and none have any clue. im going to sleep, screw my crazy teacher.

 By Virgo007 (Virgo007) on Thursday, October 09, 2003 - 05:32 pm: Edit

it is exactly the intermediate value theorem.

this may help:
http://mathforum.org/library/drmath/view/61268.html