Question

найдите производную функции у=cos x /x

Answer 1

$y(x)= frac{cosx}{x}\\y`(x)=( frac{cosx}{x})`= frac{(cosx)`*x-cosx*(x)`}{x^2}= frac{-sinx*x-cosx*1}{x^2}=-frac{x*sinx+cosx}{x^2}$