Question

найти производную
.y=-x/x^2-81

Answer 1

$y`=(- frac{x}{ x^{2} -81})`=- frac{x`cdot ( x^{2} -81)-xcdot (x^2-81)`}{(x^2-81)^2} =-frac{1cdot ( x^{2} -81)-xcdot 2x}{(x^2-81)^2} = \ \ =-frac{x^{2} -81-2x^2}{(x^2-81)^2} =frac{x^{2} +81}{(x^2-81)^2}$