问题
解答题
化简
(1)2(2a2+9b)+3(-5a2-4b)
(2)3(x3+2x2-1)-(3x3+4x2-2)
答案
(1)原式=4a2+18b-15a2-12b
=-11a2+6b;
(2)原式=3x3+6x2-3-3x3-4x2+2
=2x2-1.
化简
(1)2(2a2+9b)+3(-5a2-4b)
(2)3(x3+2x2-1)-(3x3+4x2-2)
(1)原式=4a2+18b-15a2-12b
=-11a2+6b;
(2)原式=3x3+6x2-3-3x3-4x2+2
=2x2-1.