



A.dfrac ({C)_(7)^1(C)_(5)^1}({C)_(12)^2}dfrac (2)(7)-|||-:dfrac (2)(12) B. d
(B) dfrac (1)(2)(X)_(1)+dfrac (1)(2)(X)_(2)-|||-(C) dfrac (1)(2)(X)_(1)+dfrac (1
已知_(1)=((dfrac {1)(3),-dfrac (2)(3),-dfrac (2)(3))}^T, _(2)=((-dfrac {2)(3),dfra
定积分 ^2-dfrac (1)(x)+C ()()-|||-A dfrac (1)(2)(x)^2+dfrac (1)(x)+C-|||-B dfrac (1
0 .dfrac (1)(2) .-|||--dfrac (1)(2) . .dfrac (1)(8) .dfrac (1)(6) .dfrac (1)(24)
积分 (int )_(dfrac {1)(2)}^dfrac (1{2)}(e)^npi dz=________________.(int )_(dfrac {
+dfrac (sin n)({2)^n} ;-|||-(2) _(n)=1+dfrac (1)({2)^2}+dfrac (1)({3)^2}+... +df
dfrac (1)(5)(X)_(1)+dfrac (2)(5)(X)_(2)+dfrac (2)(5)(X)_(3)-|||-D .dfrac (1)(7)(
直线dfrac (x-1)(1)=dfrac (y)(2)=dfrac (z+3)(-2)-|||-__ __-|||-__与平面dfrac (x-1)(1)=
+dfrac (1)(n(n+1)) =-|||-(3) lim _(narrow infty )(dfrac (1)(2)+dfrac (3)({2)^2}+