七年级数学下册1.18同底数幂的除法练习题(最新整理)
1.18同底数幂的除法
【课内四基达标】
1.选择题
(1)下列算式中正确的是( ).
A.(0.001)0＝0
B.(0.1)-2＝0.01
C.(10- 2×5)0＝1
D.10-4＝0.0001
(2)下列计算正确的是( ).
A.a3m-5÷a5-m＝a4 m+10
B.x4÷x3÷x2＝x3
C.(-y)5÷(-y)3＝-y2
D.m a+2b÷m b-a＝m2a+b
(3)若x2m+n y n÷x2y2=x5y,则m、n 的值分别为( )
A.m=3,n=2
B.m=2,n=2
C.m=2,n=3
D.m=3,n=1
2.填空题
(1)(-a2)3÷a3＝
(2)108÷104＝
(3)y10÷(y8÷)＝y4
(4)(5x-2y)4÷(2y-5x)2＝
1
(5)若32x-1＝1，则x＝；若3x＝
27
，则x＝.
(6)用科学记数法表示0.0001234×108＝.
3.用整数或小数表示下列各数
(1)9.932×103(2)7.21×10-5
(3)-4.21×107(4)-3.02 1×10-3
4.用科学记数法表示下列各数
(1)732400 (2)-6643919000
(3)0.00000006005 (4)-0.00000217
5.计算
(1)(x3)2÷x2÷x+x3÷(-x)2·(- x)2
1 (2)(-
2
1
)8÷［(-
2
1
)3×(-
2
)2］
(3)(x2a+3b+4c)m÷(x a)2m÷(x3)bm÷(x m)4c
(4)(x+y-z)5÷(z-x-y)3
(5)［12(x+y)3-(-x-y)3+3(-x-y)3］÷(-y-x)
【能力素质提高】
1.已知 252m÷52m-1＝125，求 m 的值.
2.已知［(2x2+3y2)2］3÷(2x2+3y2)4＝0 ，求 x、y 的值.
3.已知 x a＝24，x b=16,求x a-b的值.
【渗透拓展创新】
a m
填空：∵a m÷a m=
a m =1(a≠0)，
又∵a m÷a m=a m-m=a0(a≠0)，
∴a0＝(a 0) .
【中考真题演练】
11? 66 +12 ? 67 + 13 ? 68 + 14 ? 69 + 15 ? 70
已知 a=
11? 5 + 12 ? 6 + 13 ? 7 + 14 ? 8 + 15 ? 9
·100，问 a 的整数部分是多少?
【课内四基达标】
1.(1)D (2)D (3)C
2.(1)-a3(2)104＝10000 (3)y2
1 参考答案
(4)25x2-20xy+4y2(5)
2
，-3 (6)1.234×104
3.(1)9932 (2)0.0000721 (3)-42100000 (4)-0.003021
4.(1)7.324×105(2)-6.643919×109(3)6.005×10-8(4)-2.17×10-6
1
5.(1)2x3(2)-
8 【能力素质提高】(3)x°(4)-x2-y2-z2-2xy+2xz+2yz (5)-10x2-20xy-10y2
3
1.m＝1
2.x＝0,y＝0
3.
2 【渗透拓展创新】
1，≠
【中考真题演练】
101 提示：设 68＝m
“”
“”
At the end, Xiao Bian gives you a passage. Minand once said, "people who learn to learn are very happy people.". In every wonderful life, learning is an eternal theme. As a professional clerical and teaching position, I understand the importance of continuous learning, "life is diligent, nothing can be gained", only continuous learning can achieve better self. Only by constantly learning and mastering the latest relevant knowledge, can employees from all walks of life keep up with the pace of enterprise development and innovate to meet the needs of the market. This document is also edited by my studio professionals, there may be errors in the document, if there are errors, please correct, thank you!