- #1

karush

Gold Member

MHB

- 3,269

- 5

If $f(x)=\sin{(\ln{(2x)})}$, then $f'(x)=$

(A) $\dfrac{\sin{(\ln{(2x)}}}{2x}$

(B) $\dfrac{\cos{(\ln{(2x)}}}{x}$

(C) $\dfrac{\cos{(\ln{(2x)}}}{2x}$

(D) $\cos{\left(\dfrac{1}{2x}\right)}$

Ok W|A returned (B) $\dfrac{\cos{(\ln{(2x)}}}{x}$

but I didn't understand why the $\ln(2x)$ was not changed?

these are being also posted in MeWe in the MathQuiz group