( (int )_(dfrac {pi )(4)}^dfrac (pi {3)}dfrac (x)({sin )^2x}dx ;
设(x)=sin x, 则(dfrac (pi )(2))= __-|||-_.-|||-A cos dfrac (pi )(2)-|||-B o-|||-C-
(int )_(-dfrac {pi )(2)}^dfrac (pi {2)}dfrac (|x|sin x)(1+{cos )^3x}dx=(int )_(-
(9) (int )_(-dfrac {pi )(2)}^dfrac (pi {2)}|sin x|arctan (e)^xdx
(sin x)=dfrac (1)({cos )^2x} in (0,dfrac (pi )(2)),则(sin x)=dfrac (1)({cos )^2x}
(2) dfrac (dy)(dx)=yln dfrac (y)(x);
设(X,Y)的分布函数为(x,y)=dfrac (1)({pi )^2}(dfrac (pi )(2)+arctan dfrac (x)(2))(dfrac (
计算 lim _(xarrow dfrac {pi )(2)}dfrac (ln sin x)({(pi -2x))^2}
求lim _(xarrow dfrac {pi )(2)}dfrac (ln sin x)({(pi -2x))^2}求
1.求下列齐次方程的通解:-|||-(1) -y-sqrt ({y)^2-(x)^2}=0;-|||-(2) dfrac (dy)(dx)=yln dfrac