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Homework Help: SIMPLE QuesTion

  1. Feb 7, 2006 #1
    HI people, this will be kindergarden hw for you guys. PLease help! THANKS ALOT!

    S=integral sign

    10
    S t^3 dt=f(x)
    x

    f'(x)=?
    I say f'(x)=t^3, but it's not correct. WHY?
     
  2. jcsd
  3. Feb 7, 2006 #2

    chroot

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    First, find the indefinite integral of t3 dt, then evaluate it from t=x to t=10. Only after you've completed that can you differentiate the resultant expression with respect to x.

    - Warren
     
  4. Feb 7, 2006 #3
    so the indefinite integral of t^3 dt is t^4/4

    then evaluate it from t=x to t=10

    10^4/4-x^4/4

    then differentiate this expression

    0-x^3

    it's correct!!!!!... I am dumb THANX ALOT fOR The fAsT repLY !!!
     
    Last edited: Feb 7, 2006
  5. Feb 7, 2006 #4

    chroot

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    You're not dumb at all. See, you just learned something. :)

    - Warren
     
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