问题
解答题
化简:
(1)5a2-[a2+(5a2-2a)-2(a2-3a)];
(2)(8xy-x2+y2)-(x2-y2+8xy).
答案
(1)原式=5a2-a2-5a2+2a+2a2-6a=a2-4a;
(2)原式=8xy-x2+y2-x2+y2-8xy=2y2-2x2.
化简:
(1)5a2-[a2+(5a2-2a)-2(a2-3a)];
(2)(8xy-x2+y2)-(x2-y2+8xy).
(1)原式=5a2-a2-5a2+2a+2a2-6a=a2-4a;
(2)原式=8xy-x2+y2-x2+y2-8xy=2y2-2x2.