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Homework Help: Chain Rule

  1. Jul 31, 2010 #1
    1. The problem statement, all variables and given/known data


    2. Relevant equations

    3. The attempt at a solution

    -3sin^2(e^4(theta)) x e^4(theta)

    Just not sure what I'm doing wrong, I know what the answer is I'm just not sure how to get to it.
  2. jcsd
  3. Jul 31, 2010 #2
    For starters, you need to be clearer. Is your problem [tex] cos(e^4\theta)^3 [/tex] ? It's hard to tell from the way you wrote it. If it is, then you need to use the chain rule, which is:

    [tex] [f( g(x) )] ' = f'(g(x)) * g'(x). [/tex]
  4. Jul 31, 2010 #3
    The typical way to recall the steps if you're having trouble is:

    1. derivative of the outside function, leaving the inside function untouched.
    2. multiply by the derivative of the inside function.
  5. Jul 31, 2010 #4
    the question is cos^3 * e^4theta the theta is connected to the raised power of 4.
  6. Jul 31, 2010 #5
    You really need to use LaTeX or appropriately placed parentheses. My comments on the chain rule still apply. Where exactly are you getting stuck?
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