问题
解答题
化简:
(1)-a+2(a+b)-4(a+b)
(2)x2y-(6xy+3x2y-xy2)+(5xy+2x2y)
答案
(1)原式=-a+2a+2b-4a-4b
=-2b-3a;
(2)原式=x2y-6xy-3x2y+xy2+5xy+2x2y
=(1-3+2)x2y-(6-5)xy+xy2
=xy+xy2.
化简:
(1)-a+2(a+b)-4(a+b)
(2)x2y-(6xy+3x2y-xy2)+(5xy+2x2y)
(1)原式=-a+2a+2b-4a-4b
=-2b-3a;
(2)原式=x2y-6xy-3x2y+xy2+5xy+2x2y
=(1-3+2)x2y-(6-5)xy+xy2
=xy+xy2.