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(1)-22×7-(-3)×6+8(2)(-1)2009-(34-16-38)×24-(-2)2×3(3)5abc-2a2b-[3abc-3(4ab2+a2b)](4)14(-4x2+2x-8)-2(12x-1)(5)(2x3-xyz)-2(x3-y3+xyz)+(xyz-2y3)(6)(2x2+x)-2[x2-2(3x2-x)].

题目详情
(1)-22×7-(-3)×6+8
(2)(-1)2009-(
3
4
-
1
6
-
3
8
)×24-(-2)2×3
(3)5abc-2a2b-[3abc-3(4ab2+a2b)]
(4)
1
4
(-4x2+2x-8)-2(
1
2
x-1)
(5)(2x3-xyz)-2(x3-y3+xyz)+(xyz-2y3
(6)(2x2+x)-2[x2-2(3x2-x)].
▼优质解答
答案和解析
(1)原式=-4×7+3×6+8,
=-28+18+8,
=-2;

(2)原式=-1-
3
4
×24+
1
6
×24+
3
8
×24-4×3,
=-1-18+4+9-12,
=-18;

(3)原式=5abc-2a2b-[3abc-12ab2-3a2b],
=5abc-2a2b-3abc+12ab2+3a2b,
=2abc+a2b+12ab2

(4)原式=-x2+
1
2
x-2-x+2,
=-x2-
1
2
x;

(5)原式=2x3-xyz-2x3+2y3-2xyz+xyz-2y3=-2xyz;

(6)原式=2x2+x-2[x2-6x2+2x],
=2x2+x-2x2+12x2-4x,
=12x2-3x.