25 найти первообразную f(x) f(x)=x^2+4x f(x)=cos(3x-5) f(x)=1-2x+x^3

1) F(x) = ((x^3)/3) + 4*(x^2/2) + C = (x^3/3) + 2*(x^2) + C.
2) F(x) = (1/3)*sin(3x-5) + C,
Проверка ( (1/3)*sin(3x-5) + C)' = (1/3)*cos(3x-5)*(3x-5)' = (3/3)*cos(3x-5)=
= cos(3x-5).
3) F(x) = x - 2*(x^2/2) + (x^4/4) + C = x - x^2 + (x^4/4) + C