# [SOLVED] Chain Rule

• Nov 4th 2005, 03:46 AM
trunks super saiyan
[SOLVED] Chain Rule
Let f:R ---> R be a differentiable funtion. For all real values of x, the derivative of f(e^(2x)) with respect to x will be equal to
A. 2e^(2x) f'(x)
B. e^(2x) f'(x)
C. 2e^(2x) f'(e^2x)
D. 2f'(e^(2x))
E. f'(e^(2x))

"i put E. down but some say it is c, which is correct and y?
• Nov 4th 2005, 04:09 AM
Jameson
Quote:

Originally Posted by trunks super saiyan
Let f:R ---> R be a differentiable funtion. For all real values of x, the derivative of f(e^(2x)) with respect to x will be equal to
A. 2e^(2x) f'(x)
B. e^(2x) f'(x)
C. 2e^(2x) f'(e^2x)
D. 2f'(e^(2x))
E. f'(e^(2x))

"i put E. down but some say it is c, which is correct and y?

I think I saw you post this on physicsforum.com.

The answer is C, because of the chain rule. Any time you have a composite function, the derivative is taken like so: $\displaystyle \frac{d(f(g(x))}{dx}=f'(g(x))*g'(x)$

Your question follows the same logic. It is C.

Jameson