The problem I have is to differentiate $ y = ln(x^4)$
Using the rule : $\frac{d[lnf(x)]}{dx}=\frac{f'(x)}{f(x)}$ My working is: $\frac{dy}{dx} = \frac{x^4ln(x)}{x^4}$ $=ln(x)$
but the book is giving the answer : $\frac{4}{x}$
Please help because I am confused