14.1.3 积的乘方课课练(人教版八年级数学上册)
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2022-09-13 19:01:02
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第十四章整式的乘法与因式分解14.1整式的乘法
14.1.3积的乘方1.计算(–x2y)2的结果是( )
A.x4y2B.–x4y2
C.x2y2D.–x2y22.下列运算正确的是()
A.x•x2=x2B.(xy)2=xy2
C.(x2)3=x6D.x2+x2=x4
3.计算:(1)82024×0.1252023=________;
(2)(-3)2023×(-)2022________;
(3)(0.04)2023×[(–5)2023]2=________.
4.判断:(1)(ab2)3=ab6()(2)(3xy)3=9x3y3()(3)(–2a2)2=–4a4()(4)–(–ab2)2=a2b4()
5.计算:
(1)(ab)8;(2)(2m)3;(3)(–xy)5;
(4)(5ab2)3;(5)(2×102)2;(6)(–3×103)3.
\n6.计算:(1)2(x3)2·x3–(3x3)3+(5x)2·x7;
(2)(3xy2)2+(–4xy3)·(–xy);
(3)(–2x3)3·(x2)2.7.如果(an•bm•b)3=a9b15,求m,n的值.\n参考答案:1.A2.C3.(1)8;(2)-3;(3)14.(1)×(2)×(3)×(4)×5.解:(1)原式=a8b8;
(2)原式=23·m3=8m3;
(3)原式=(–x)5·y5=–x5y5;
(4)原式=53·a3·(b2)3=125a3b6;
(5)原式=22×(102)2=4×104;
(6)原式=(–3)3×(103)3=–27×109=–2.7×1010.
6.(1)解:原式=2x6·x3–27x9+25x2·x7
=2x9–27x9+25x9=0;
(2)解:原式=9x2y4+4x2y4
=13x2y4;
(3)解:原式=–8x9·x4=–8x13.7.解:∵(an•bm•b)3=a9b15,
\∴(an)3•(bm)3•b3=a9b15,
\∴a3n•b3m•b3=a9b15,
\∴a3n•b3m+3=a9b15,
\∴3n=9,3m+3=15.
\n\∴n=3,m=4.