Question

y= cosx/x² найти производную функции

Answer 1

$y= \frac{cosx}{x^2}$

$y'= \frac{x^2(cosx)'-(x^2)'cosx}{x^4} = \frac{-x^2sinx-2xcosx}{x^4} =\frac{-x(xsinx+2cosx)}{x^4}= \\ \\ =\frac{-(xsinx+2cosx)}{x^3} =- \frac{xsinx+2cosx}{x^3}$