(1) int (x)^2arctan xdx;
int (x)^2arctan xdx; ;
int (x)^2arctan xdx
(18)int x^2arctan xdx.(18)$\int x^{2}\arctan xdx$.
(int )_(0)^1arctan dfrac (x)(2)dx=()(int )_(0)^1arctan dfrac (x)(2)dx=()(int )_(
13.计算不定积分 int dfrac ({x)^2arctan x}({x)^2+1}dx
求dfrac (d)(dx)[ (int )_(2)^eln xdx] =________.求________.
(5) int dfrac (arctan x)(1+{x)^2}dx= __
(9) (int )_(-dfrac {pi )(2)}^dfrac (pi {2)}|sin x|arctan (e)^xdx
[题目]计算 (int )_(1)^+infty dfrac (arctan x)({x)^2}dx