=(1+(x)^2)arctan x;

(5) int dfrac (arctan x)(1+{x)^2}dx= __

求下列初值问题的解：(dfrac (1+{x)^2}(2))y=arctan x，(dfrac (1+{x)^2}(2))y=arctan x.（ ）求下列初值

(9) int dfrac (x{e)^arctan x}({(1+{x)^2)}^dfrac (3{2)}}dx ;

证明等式 arctan x=arcsin dfrac (x)(sqrt {1+{x)^2}} , in (-infty ,+infty

7.不定积分 int dfrac (arctan x)({x)^2(1+(x)^2)}dx= __

1、设 =ln (arctan sqrt (1+{x)^2}) 求dy;

(19) int tan sqrt (1+{x)^2}cdot dfrac (xdx)(sqrt {1+{x)^2}}-|||-(20) int dfrac (

(19) int tan sqrt (1+{x)^2}cdot dfrac (xdx)(sqrt {1+{x)^2}}-|||-(20) int dfrac (

第四章 不正积分-|||-(20)arctan√x/dx;-|||-(10) sqrt (18sqrt {1+{x)^2}}cdot dfrac (xsqrt

讨论下列函数的有界性：(1) (x)=dfrac (x)(1+{x)^2}-|||-(2) (x)=dfrac (1+{x)^2}(1+{x)^4}讨论下列函数