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1、人教版八年级数学上册15.2.1分式的乘除同步测试题带答案学校:_班级:_姓名:_考号:_一、单选题1计算x2y3的结果是( )Ax6yBx6y3Cx5y3Dx8y32下列计算错误的是()Ayx2y2x=1xyB3x2y22y3x3=2y3xCxyx22xy+y2xy2+x2yx2y2=1xyDx2+xx2+2x+1x21x1=xx+13化简m1mm1m2的结果是()Am1BmC1mD1m14化简3x+6x22xx24x2+4x+4的结果为()A3B3xC13Dx35计算2ab222ba22b2a的结果是()A8ab4B8ab4C16ab4D16ab46化简:16a2a2+4a+4a42a+4
2、a2a+4,其结果是()A2B2C2a2a+2D2a+227若x=2023,则式子x22x+1x21x1x2+x的值为()A2021B2022C2023D18灰太狼在跑一段山路时,上山速度是80米/分,到达山顶后再下山,下山的速度是上山速度的3倍,如果上、下山的路程相同,那么灰太狼跑这段山路的平均速度是()A160米/分B140米/分C60米/分D120米/分二、填空题9xA2=x2(y+1)6,那么A= 10计算3np2mnp2的结果是 11计算9x2x+22x+4x23x的结果是 12若a8b4=16,则a3b22ab32的值为 13若3xx2y2A=1x+y,则A等于 14化简a+bab
3、1ab= 15若m等于它的倒数,则m2+4m+4m24m2+2mm2的值为 16已知a0,S1=3a,S2=3S1,S3=3S2,S4=3S3,S2024=3S2023,则S2024= 三、解答题17计算:(1)4a2ba2b2b8a;(2)a2bc3c2ab2bca4;(3)x2y2xy2x+yxxy318计算:(1)x4x12x28x+16x1x21x+2;(2)a2b2ab3aab2a+b3ab19计算:(1)a+2a22a+1a24a+4a+1a24a21;(2)x21x2+2x+12x224x2+8x+4x1220已知A=x+2x26x+94x2x29x2x+3(1)化简A;(2)若
4、x满足不等式组2x4x3x22,设两块草坪面积分别为S甲、S乙(1)比较甲、乙两块草坪面积的大小;(2)求甲、乙两块草坪的面积的比参考答案题号12345678 答案BDBBACCD 1解:x2y3=x6y3,故选:B2解:A. yx2y2x=yx2xy2=1xy,计算正确,该选项不符合题意;B. 3x2y22y3x3=9x24y28y327x3=2y3x,计算正确,该选项不符合题意;C. xyx22xy+y2xy2+x2yx2y2=xyxy2x+yxyxyx+y=1xy,计算正确,该选项不符合题意;D. x2+xx2+2x+1x21x1=xx+1x+12x+1x1x1=x,计算错误,该选项符合
5、题意;故选:D3解:原式=m1mm2m1=m.故选:B4解:3x+6x22xx24x2+4x+4=3x+2xx2x+2x2x+22=3x,故选:B5解:2ab222ba22b2a=4a2b44b2a22b2a=4a2b44b2a2a2b2=8ab4故选:A6解:16a2a2+4a+4a42a+4a2a+4=4a4+aa+222a+2a4a2a+4=2a2a+2故选:C7解:原式=x22x+1x21x2+xx1=(x1)2(x+1)(x1)x(x+1)x1=x,将x=2013代入原式可得:原式=2013,故选:C8解:设上坡的路程为S,则上、下坡的总路程为2S,上坡时间为S80,下坡时间为S80
6、3=S240,总时间为S80+S240=S60,所以平均速度为2SS60=120(米/分)故选D9解:xA2=x2(y+1)6=x2(y+1)32=xy+132=xy+132,A=y+13故答案为:y+1310解:3np2mnp2=9np22p2mn=9nm,故答案为:9nm11解:9x2x+22x+4x23x=3+x3xx+22x+2xx3=2x+6x,故答案为:2x+6x12解:a3b22ab32=a6b4b6a2=a4b2因为a8b4=16,所以a4b22=16,所以a4b2=4(a4b2=4舍去),所以a3b22ab32=4故答案为:413解:3xx2y2A=1x+y,A=3xx2y2
7、1x+y=3xx+yxyx+y=3xxy,故答案为:3xxy14解:a+bab1ab=a+b1ab1ab=a+bab2=a+ba22ab+b2故答案为:a+ba22ab+b215解:m2+4m+4m24m2+2mm2,原式=m+22m+2m2m2mm+2,=1m, m等于它的倒数, m=1,原式=1m=1,故答案为:116解:S1=3a,S2=3S1,S3=3S2,S4=3S3,S2024=3S2023,S2=3S1=33a=1a,S3=3S2=31a=3a,S2n=1a,S2n1=3a(n为正整数),S2024=1a;故答案为:1a17解:(1)4a2ba2b2b8a=4a2ba24b2b8
8、a=4a2b4b2a2b8a=2b4a;(2)a2bc3c2ab2bca4=a6b3c3c4a2b2b4c4a4=a6b3c3c4a2b2a4b4c4=a8b3c3;(3)x2y2xy2x+yxxy3=x+y2xy2x2y21x+yx3xy3=xx+yy2xy=x2+xyxy2y318(1)解:x4x12x28x+16x1x21x+2=x42x12x1x42x+1x1x+2=x+1x+2;(2)解:a2b2ab3aab2a+b3ab=a+b3ab3a3b3a2ab2aba+b3=ab2ab319(1)解:a+2a22a+1a24a+4a+1a24a21=a+2a12a22a+1a+1a1a+2a2=a2a1;(2)解:x21x2+2x+12x224x2+8x+4x12=x+1x1x+124x+122x+1x11x12=x+1x1x+124x+122x+1x11x12=2x1220(1)解:A=x+2x26x+94x2x29x2x+3=x+2x32x+3x32+x2xx2x+3=1x3;(2)解:2x4x3x21,解得:12,m220,BA;(2)S甲S乙=m242m24m=m+2m22mm2=m+22m所以甲、乙两块草坪的面积的比为m+22m第 7 页 共 7 页