Question

What's the derivative of the function y=f(2+lnx) ?
The options are:
A) y'=2/x*f'(2+lnx)
B) y'=1/x
C) y'=1/x*f'(2+lnx)
D) y'=2+lnx

Answer 1

Differentiate both sides, but be careful to use the chain rule correctly on the right hand side. This will give you:\[y'=\frac{df}{dx}\frac{d(2+lnx)}{dx}\]

Answer 2

Which is simply \[y'=\frac{1}{x}f'\], or choice C

Answer 3

Thank you !

Answer 4

Sure thing