12幂的乘方专项练习50题(有答案过程)
知识点: 12幂的乘方专项练习50题
1.若m、n均为正整数,则(a)=_____,即幂的乘方,底数_____,指数_______.
2.计算:
(1)(7)=_______; (2)7×7=_______;
(3)(x5)2=_______; (4)x5·x2=________;
(5)[(-7)]=_______; (6)[(-7)]=________.
3.你能说明下面每一步计算的理由吗?将它们填在括号里.
(1)y·(y2)3
=y·y6 ( )
=y ( )
(2)2(a)-(a)
=2a12-a12 ( )
=a12 ( ) 263474 55 45454mn
专项练习:
(1)[(a+b)2] 4= (2)-(y4)5=
(3)(y2a+1)2 (4)[(-5)3] 4-(54)3
(5)(a-b)[(a-b)2] 5
(6)(-a2)5·a-a11
(7)(x6)2+x10·x2+2[(-x)3] 4
(8)(-x5)2=_______,(-x2)5=________,[(-x)2] 5=______.
(9)(a5)3 (10)(an-2)3 (11)(43)3
(12)(-x) (13)[(-x)] (14)[(x-y)]
352 33 4
(15)(a4)2(a2)3______________
(16)(16)(a3)2(a)3____________;
(17)(x4)5(x5)4___________,
(18)(am1)3(a2)1m_______________
(19)3(x2)2(x2)4(x5)2(x2)2__________ _________
(20)若 xn3, 则x3n
(21)x·(x2)3
(22)(xm)n·(xn)m
(23)(y4)5-(y5)4
(24)(m)+mm+m·m·m
3410238 (25)[(a-b)n] 2 [(b-a)n-1] 2
(26)若2k=83,则k=______.
(27)(m3)4+m10m2-m·m3·m8
(28)5(a3)4-13(a6)2 =
(29)7x4·x5·(-x)7+5(x4)4-(x8)2
(30)[(x+y)]+[(x+y)]
(31)[(b-3a)2]n+1·[(3a-b)2n+1]3(n为正整数)
(32)x3·(xn)5=x13,则n=_______.
34433223(33)(x)+(x)=________,(a)·(a)=_________.
(34)若xm·x2m=2,求x9m 3692
(35)若a=3,求(a)2n3n4
(36)已知am=2,an=3,求a2m+3n
(37)若644×83=2x,求x的值。
(38)若2×8n×16n=222,求n的值.
(39)已知a2m=2,b3n=3,求(a3m)2-(b2n)3+a2m·b3n的值.
(40)若2x=4y+1,27y=3x- 1,试求x与y的值.
(41)已知:3x=2,求3x+2的值.
(42) 已知xm+n·xm-n=x9,求m的值.
(43)若5
(44)已知am=3,an=2,求am+2n的值;
(45)已知a2n+1=5,求a6n+3的值.
(46)已知a=3555,b=4444,c=5333,试比较a,b,c的大小.
(47)当n为奇数时,(-a2)n·(-an)2=_________.
(48)已知164=28m,求m的值。
(49)-{-[(-a2)3] 4}2=_________.
(50)已知n为正整数,且x2n=3,求9(x3n)2的值. 2x+1=125,求(x-2)2011+x的值.
(51)若│a-2b│+(b-2)=0,求ab的值.
xy(52)已知3x+4y-5=0,求8×16的值.
(53)若n为自然数,试确定3-1的末位数字.
5025(54)比较5与24的大小。
(55).灵活运用幂的乘方法则和同底数幂的乘法法则,以及数学中的整体思想,还可以解 决较复杂的问题,例如:已知a=3,a=2,求axyx+y4n2510的值.
根据同底数幂乘法的逆运算,设a2x+3y=a2x·a3y,然后利用幂的乘方的逆运算, 得a= (a),a=(a),把a=3,a=2代入即可求得结果.
所以a2x+3y=a2x·a3y=(ax)2·(ay)3=32·23=9×8=72.
试一试完成以下问题:
已知am=2,an=5,求a3m+2n的值.
2xx23yy3xy