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计算:(1)(-2x2y3)2•(xy)3(2)(2x+y-1)2(3)59.8×60.2(4)(65a3x4−0.9ax3)÷35ax3(5)(7x2y3-8x3y2z)÷8x2y2(6)1213÷(310×411)(7)4(x+1)2-(2x+5)(2x-5)(8)2x(12x−1)−3x(13x+23).

题目详情
计算:
(1)(-2x2y32•(xy)3
(2)(2x+y-1)2
(3)59.8×60.2
(4)(
6
5
a3x4−0.9ax3)÷
3
5
ax3
(5)(7x2y3-8x3y2z)÷8x2y2
(6)1213÷(310×411
(7)4(x+1)2-(2x+5)(2x-5)
(8)2x(
1
2
x−1)−3x(
1
3
x+
2
3
).
▼优质解答
答案和解析
(1)原式=4x4y6•x3y3
=4x7y9

(2)原式=[(2x+y)-1]2
=(2x+y)2-2(2x+y)•1+12
=4x2+4xy+y2-4x-2y+1;

(3)原式=(60-0.2)×(60+0.2)
=602-0.22
=3600-0.04
=3599.96;

(4)原式=
6
5
a3x4÷
3
5
ax3-0.9ax3÷
3
5
ax3
=2a2x-1.5;

(5)原式=7x2y3÷8x2y2-8x3y2z÷8x2y2
=
7
8
y-xz;

(6)原式=1213÷(310×410×4)
=1213÷(1210×4)
=
1
4
×123
=432;

(7)原式=4(x2+2x+1)-(4x2-25)
=4x2+8x+4-4x2+25
=8x+29;

(8)原式=x2-2x-x2-2x
=-4x.