化简:(1)(5x2y-7xy2)-(xy2-3x2y)(2)8a2+4ab-4(2a2+12ab).
题型:解答题难度:一般来源:不详
化简: (1)(5x2y-7xy2)-(xy2-3x2y) (2)8a2+4ab-4(2a2+ab). |
答案
(1)原式=5x2y-7xy2-xy2+3x2y =8x2y-8xy2;
(2)原式=8a2+4ab-8a2-2ab =2ab. |
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