问题
解答题
化简:
(1)x-2y+(2x-y);
(2)(3a2-b2)-3(a2-2b2).
答案
(1)原式=x-2y+2x-y
=x+2x-2y-y
=3x-3y,
(2)原式=3a2-b2-3a2+6b2
=5b2.
化简:
(1)x-2y+(2x-y);
(2)(3a2-b2)-3(a2-2b2).
(1)原式=x-2y+2x-y
=x+2x-2y-y
=3x-3y,
(2)原式=3a2-b2-3a2+6b2
=5b2.