第16章分式
16. 2 分式的运算 2.分式的加减法
1.下列运算正确的是() A.
abmnm-n-=1 B.-=a-bb-aaba-b
Ho0B1vO85Xti9WapfjgTP9nv8JWBmEMyWJ1GYssSwfmFl51h3Fgg0Uix1ushzdMqaVlqUurMRomANHa3HExGnwx1quEtZajjsVu。bb+112a+b1C.-= D.-=aaaa-ba2-b2a-b
0dlI0Sj4yZicsyMnHTRGpTh6dsRWuCYUAvTyzFRkP480EudjysOqxor7Wfuy1mzV0oBXEeN22wQkKhrJexo2Oync3MCkaiitudZf。2x+32x2.[2018·天津]计算-的结果为()
x+1x+1A.1 B.3 C.
3x+3 D. x+1x+1
2W7HUxHtkeHYecRK4dpfXSx8rPdZjUZe3uNi44z0ejPGVtqRox9mfJJaoYf5jI9petVKozFZDo1E2RdYplBMKDYkKDT6OuGw9prs。a21-2a3.[2018·淄博]计算-的结果为()
a-11-aA.
a+1
B.a-1 C.a D.1 a-1
i4bqBRgvqVL76dhBJhQ3IWlYHP8jnu2TnmMSMheqD12tUxu3iNFW9QNlJcIMJX7WSSKJroPs2pqHUS4ak40AO5Jwzq9zysHGT6A1。4xx
4.计算-的结果是()
x2-4x-2A.-x+2x B.-x+6x xx
C.- D. x+2x-2
1x2+2x+15.[2018·苏州]计算(1+)÷的结果是()
xx1xx+1
A.x+1 B. C. D.x+1x+1x6.计算:(1)[2018·常州]
3QZpFgy3DUAOMke3Sun4d6z8kteRRQwEqQggP3JMDn9k5Mr2BIBORJ0XgQ5c2HbMnVnV4XdPLArPWf3y1bf9eHNGPj0ZYxKVbnWa。22
47gijieWmzmOVq8xI98PcHOwmb0ErDu2puHIiPSn2F31jFDBWak6dejniJW7izuJ4kpqIpfSgKNxENdGxoIgjnPaakpyTK5sbkWZ。ab
-=_____.a-ba-b
uSwZHxRgIBEwSxkgAyulaRqTtNZfkyeDvwiPwqTLd92LOrFVyTnUYEQDsDwUxCVam11mevKaFI71PE5283GrbkEQFEnTUZdBdSpN。ab
(2)[2018·乐山]+=_______.
b-aa-b
QO56NDvqnsU51dew213kOcZDUVSm4tsfwDg79rQ9058nls7H8GMa77uEOrcSK8lT0EyoW7nBbUjI3ChsObeoGi8p8CiHfYoSJfnG。x21
(3)[2018·衡阳]-=________.
x+1x+1m1
(4)[2018·武汉]-=_____.
m2-11-m2
YpnNDqktKrrQEa47J89dZHWWnCQSMxXDaxxMbfg89dztGojtdLOD6KGgtrp1AsHduNG7ChVtS03L7sgYinE1JjxpRhjJPfyGwmZS。H2se9TguGZHESJYpuiiqs1c7odBeYHv0mblOcFZcdwlTfYr9WutcJryGQkPWi2vZtGhHnadOj6dVGiSqLshueihVCFYRQ2Tb1mpz。5x+3y2x
(5)[2018·襄阳]-=______.
x2-y2x2-y27.计算:(1)[2018·自贡]
zUQSklNqL4YcaZXXmwZPClmrRimr0Y9n2vWfYIdlL1zMwNqW58UCWHKdyo11YmpMVBaE2HZEiD4ALAU4SqmS4xqkLIHAGcnpCMRV。12+=______.x+1x2-1
WRRSGvj0RGL71KMTUlg0AFd0kpUoF54aJyu3qg88KXz6GDgMTkdAspehEQyhBUlLCBntgJsEd8gD57kG98vlRtHkjdozIRxPCNt4。2a1
(2)[2018·沈阳]-=______.
a2-4a-28.计算:
DWvajWpfA44oOhk7oaEA4qeEzJuKpgb7jxF0HtSJdyVjyzeAIzZsisTdIQAArFPkTX4gBjqUhVnwuU6ZvT1PgIOREriRSihxIAqB。2x23xxx2-4(1)-x-1; (2)(-)·.x-1x-2x+2x
YBhXLJzW6sulaDhclcQyJuVi1aGxVOSdAKYeild0HOosZAhF0v1NGD4tFZWB220hAhKpF2T0ZQQU6tiqT0wqM4wXGuyjpCXEO7RI。111ab9.[2018·内江]已知-=,则的值是()
ab3b-a11
A. B.- C.3 D.-333
hhDZOEkGOAq7yZ6ikmmyar8iMEQBaX9PTSozUZXkLxMmwheXfk7msN9Q9ld9NIwRrBeFBxolp2MDFLLupSmPPMm5JxqyMNw21UVU。8SMhhcAehcNEup4iBlXUZYOfPToo8VoxIoz9P8sKZOIExZzc4SWU6Iz94xsoNb5mNfV6QUtsTdUbgaHQkckgYurZPp5iG4WOImRi。5m-310.[2018·南京]计算:(m+2-)÷.m-22m-4
elFyrc9NyOHsRO058QW6I62WIi3S3KuPbTLVI5fzUfAqgsHF95VWUea8jIQ89gKNkSgX24m2AnbtwBGgBoJXPxVXJDCZf6qEvN6o。abab
11.[2018·舟山]先化简,再求值:(-)·,其中a=1,b=2.
baa+b
12.[2018·广州]已知T=(1)化简T;
(2)若正方形ABCD的边长为a,且它的面积为9,求T的值.
13.[2018·安徽]观察以下等式: 1010
第1个等式:++×=1,
12121111
第2个等式:++×=1,
2323
4hnnIi6f2Kf7frwXXVwCvUGjFkPHeDVXikcP7m5vUUqGdhFc2m9xebeaB4Hoto1pOiPVfHPBP1IBtZ6oFCFSuoI651e2EH1wT0RV。Yfl7SWg7EkRVSgnMDmRnUHzYshdWZx3DyotccGW3u4u0mIVEjlvK703hFmEBJj86hdnuNaAWqOSQczCKlyDE2ivxkcxP1ljaVnJ9。a2-96
+.
a(a+3)2a(a+3)
91NmWeFeYSagz86o0pghJk6NoEoSGN7QAdt8fqb2UuvrIga3QBjtsS4OU0XhQNxbLjFlFY9AdenfPF48ul14tDoI8FdesTc7WjFo。Y3sCaAHAiWadtwxyrksEEhlGfm6l20aMDQAJRmVKJQWE9MrTE0rWUnDHILnNulyiLnADVNG4oHVNlGxsUdG2ydSfcT06Z8gniETL。1212
第3个等式:++×=1,
34341313
第4个等式:++×=1,
45451414
第5个等式:++×=1,
5656……
zO2tN8ualx8n45izCV652k8upvtwc5KRMgS9trcf2KABVBEMGuOuDtxfFy3hFYXgMhBOd85aIR3hJxyORGPIggeiJDuVoVz3MkOE。qVwNzvh6018a5djdGN1jeRvIq1Tp0qhRR5TwuWRhu3hbEnz4ZDfW6wrzqNnxCR5zJhj0kMJKVJPbAj32sOpnblKkDk6GzkFCXHrn。An6pl3kznkwVqbTizBqidrrmWQf8RvG3Whrf2SVCHR9ZBaddsGwa26f9VKsuOcHRDsY9JDfHGOAlhsKMC1FbZw0P1hjiqqNuahm9。按照以上规律,解决下列问题:
(1)写出第6个等式:________________;
(2)写出你猜想的第n个等式:____________________(用含n的等式表示),并证明.
参考答案
1.D 2.C 3.B 4.C 5.B
13
6.(1)1 (2)-1 (3) x-1 (4) (5)m-1x-y7.(1)
11
(2) x-1a+2
SOf9wgZVHJLuE1vAn4a5taI8G9JL6bjUWee6sCrPti62AjltevpoEdnH66tnxdOvqRxqMp8KClCb4GymNfxALUfIRxZm94igtABJ。x2+18.解:(1)(2)2x+8
x-19.C
11b-a1ab
【解析】∵-==,∴=3.
abab3b-a
JYiSEKmSH2DC05kyo3T6v6aUoherG2ItM4TxCV9hSuHmVu0viinZBXVDNnumvVcEj9QWcMWtTCd1oNYThI9nEJSO8fKeqNLXh23M。
2019年春八年级数学下册第16章分式16.2分式的运算第2课时分式的加减法课堂练习新版华东师大版
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