Question

Помогите решить!!!!
По матану

Answer 1

$y=-x*cos(x)$
$(UV)'=U'V+UV'$
$y'=(-x)'cos(x)+(-x)(cos(x))'$
$y'=-cos(x)-x(-sin(x))=-cos(x)+x*sin(x)$

$y''=(-cos(x))'+((x)'sin(x)+x(sin(x)'))$
$y''=sin(x)+sin(x)+x*cos(x)=2sin(x)+x*cos(x)$