1、 同底数幂的除法专项练习30题(有答案)1 计算:(2 m2)3+m7m2计算:3(x2)3x3(x3)3+(x)2x9x23已知am=3,an=4,求a2mn的值4已知3m=6,3n=3,求32m3n的值5已知2a=3,4b=5,8c=7,求8a+c2b的值6如果xm=5,xn=25,求x5m2n的值7计算:anan+5a7(n是整数)8计算:(1)m9m3;(2)(a)6(a)3;(3)(8)6(8)5;(4)62m+36m93336(3)810把下式化成(ab)p的形式:15(ab)36(ab)p+5(ba)245(ba)511计算:(1)(a8)2a8;(2)(ab)2(ba)2n(a
2、b)2n112(a2)3(a2)4(a2)513计算:x3(2x3)2(x4)214若(xmx2n)3xmn与4x2为同类项,且2m+5n=7,求4m225n2的值15计算:(1)m9m7=_;(2)(a)6(a)2=_;(3)(xy)6(yx)3(xy)=_16已知2m=8,2n=4求(1)2mn的值(2)2m+2n的值17 (1)已知xm=8,xn=5,求xmn的值; (2)已知10m=3,10n=2,求103m2n的值18已知am=4,an=3,ak=2,求am3k+2n的值_19计算:(3x2n+2yn)3(x3y)2n20已知:an=2,am=3,ak=4,试求a2n+m2k的值21
3、已知5x3y2=0,求1010x106y的值22已知10a=2,10b=9,求:的值23已知,求n的值24计算:(a2n)2a3n+2a225已知am=2,an=7,求a3m+2na2n3m的值26计算:(2)3(2)2(2)827(a)5(a3)4(a)228已知ax=4,ay=9,求a3x2y的值29计算(1)a7a4(2)(m)8(m)3(3)(xy)7(xy)4(4)x2m+2xm+2(5)(xy)5(yx)3(6)x6x2x30若3292a+127a+1=81,求a的值同底数幂的除法50题参考答案:1(2m2)3+m7m,=(2)3(m2)3+m6,=8m6+m6,=7m623(x2
4、)3x3(x3)3+(x)2x9x2=3x6x3x9+x2x9x2=3x9x9+x9=3x93am=3,an=4,a2mn=a2man=(am)2an=324=43m=6,3n=3,32m3n=32m33n=(3m)2(3n)3=62(3)3=52a=3,4b=5,8c=7,8a+c2b=23a+3c6b=(2a)3(23)c(22b)3=277125=6xm=5,xn=25,x5m2n=(xm)5(xn)2=55(25)2=5554=57anan+5a7=a2n+57=a2n28(1)m9m3=1m93=m6; (2)(a)6(a)3=(a)63=(a)3=a3; (3)(8)6(8)5=(
5、8)65=(8)1=8; (4)62m+36m=6(2m+3)m=6m+393336(3)8=3938=310. 15(ab)36(ab)p+5(ba)245(ba)5 =15(ab)36(ab)p+5(ab)245(ab)5 =15(6)(45)(ab)3+p+2+55=2(ab)p+511(1)(a8)2a8=a16a8=a168=a8; (2)(ab)2(ba)2n(ab)2n1=(ab)2(ab)2n(ab)2n1=(ab)2+2n(2n1)=(ab)312(a2)3(a2)4(a2)5=a6a8(a10)=a14a10=a413x3(2x3)2(x4)2=4x9x8=4x14(xmx
6、2n)3xmn=(xm2n)3xmn=x3m6nxmn=x2m5n,因它与4x2为同类项,所以2m5n=2,又2m+5n=7, 所以4m225n2=(2m)2(5n)2=(2m+5n)(2m5n)=72=1415. (1)m9m7=m97=m2;(2)(a)6(a)2=(a)62=a4; (3)(xy)6(yx)3(xy)=(xy)6(xy)3(xy)=(xy)631=(xy)2162m=8=23,2n=4=22,m=3,n=2,(1)2mn=232=2;(2)2m+2n=23+4=27=12817(1)xm=8,xn=5,xmn=xmxn,=85=;(2)10m=3,10n=2,103m=(
7、10m)3=33=27,102n=(10n)2=22=4,103m2n=103m102n=274=18am=4,an=3,am3k+2n=ama3ka2n=am(ak)3(an)2=42332=19(3x2n+2yn)3(x3y)2n=27x6n+6y3n(x3y)2n=27x6n+6y3nx6ny2n=27x6yn20an=2,am=3,ak=4,a2n+m2k=a2nama2k=(an)2am(ak)2=4316=21由5x3y2=0,得5x3y=21010x106y=1010x6y=102(5x3y)=1022=104 故1010x106y的值是10422=10 2ab=2332m+2=
8、(32)m+1=9m+1,9m3m+2=9m9m+1=91=()2,n=224(a2n)2a3n+2a2=a4na 3n+2a2=a4n3n2a2=a n2a2=an2+2=an25am=2,an=7,a3m+2na2n3m=(am)3(an)2(an)2(am)3=849498=26(2)3(2)2(2)8=(2)5(2)8=(2)58=(2)3=27原式=(a)5a12(a)2=a5+12(a)2=a17a2=a15故答案为:a1528a3x2y=(ax)3(ay)2=4392=29(1)a7a4=a3; (2)(m)8(m)3=(m)5=m5; (3)(xy)7(xy)4=(xy)3=x3y3; (4)x2m+2xm+2=xm; (5)(xy)5(yx)3=(yx)5(yx)3=(yx)2; (6)x6x2x=x4x=x530原式可化为:3232(2a+1)33(a+1)=34,即2+2(2a+1)3(a+1)=4,解得a=3故答案为:3