化简:(1)4x2-8x+5-3x2+6x-2;(2)3x3-(-5x2+3x3)+2(-2x2+x)
题型:解答题难度:一般来源:不详
化简: (1)4x2-8x+5-3x2+6x-2; (2)3x3-(-5x2+3x3)+2(-2x2+x) |
答案
(1)4x2-8x+5-3x2+6x-2 =(4-3)x2+(-8+6)x+(5-2) =x2-2x+3;
(2)3x3-(-5x2+3x3)+2(-2x2+x) =3x3+5x2-3x3-4x2+2x =(3-3)x3+(5-4)x2+2x =0+x2+2x =x2+2x. |
举一反三
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