Question

Найти f" ( х ), если: 1). f ( х ) = х^2 cos х;

Answer 1

y`=-2x sin(x) y``=-2cos(x)

Answer 2

f(x)=x^2cosx f ' (x)=2xcosx -x^2sinx f '' (x) = 2cos(x)-2xsinx -2xsinx - x^2cosx=2cos(x)-4xsinx - x^2cosx