问题 解答题
化简:
(1)(5a2+2a-1)-4(3-8a+2a2
(2)3x2-[5x-(
1
2
x-3)+2x2]
答案

(1)原式=5a2+2a-1-12+32a-8a2=-3a2+34a-13;

(2)原式=3x2-(5x-

1
2
x+3+2x2)=3x2-5x+
1
2
x-3-2x2=x2-
9
2
x-3.

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