Question

Помогите решить производную

Answer 1

$y= frac{3x}{1+x^2} \\y'= frac{3(1+x^2)-3xcdot 2x}{(1+x^2)^2}= frac{3-3x^2}{(1+x^2)^2}$

Answer 2

$y'= frac{3(1+ x^{2} )-6 x^{2} }{(1+ x^{2} )^{2} }$

$y'= frac{3-3 x^{2} }{(1+ x^{2} )^{2} }$