Question

find the derivative of y = x cos x​

Answer 1

Answer:

$f(x) = xcosx \\ \\ f'(x) = x \frac{d}{dx} (cosx) + cosx \frac{d}{dx} (x) \\ \\ \: \: \: \: \: \: \: \: \: = x( - sinx) + cosx(1) \\ \\ \: \: \: \: \: \: \: = - sinx + cosx$