题目内容
-÷6+×3
计算:+-
计算
(x+y)(x-y-1)
解方程:-=.
()÷〔-()-〕
计算:…….
计算:
÷(a+3)×÷
(1)x+1- (2)-
(3)- (4)-
(5)- (6)-+
(1)(x2+y)(x2-y)-(-x)2·(-x2);
(2)[(x-y)2+(x+y)2](x2-2y2).