int x^2 arcsin(x)dx = ?

1 Answer
Dec 28, 2016

1/3x^3arcsin(x)+1/9x^2sqrt(1-x^2)+2/9sqrt(1-x^2)+C

Explanation:

d/(dx)(x^3 arcsin(x))=3x^2arcsin(x)+x^3/sqrt(1-x^2) then

int x^2 arcsin(x)dx = 1/3x^3 arcsin(x)-1/3int x^3/sqrt(1-x^2)dx

now d/(dx)(x^2sqrt(1-x^2))=2 x sqrt[1 - x^2]-x^3/sqrt[1 - x^2]

so

int x^3/sqrt(1-x^2)dx=int 2 x sqrt[1 - x^2]dx-x^2sqrt(1-x^2)

and

int 2 x sqrt[1 - x^2]dx=-2/3 (1 - x^2)^(3/2)

putting all together we have

int x^2 arcsin(x)dx=1/3x^3arcsin(x)+1/9x^2sqrt(1-x^2)+2/9sqrt(1-x^2)+C