内容正文:
计算专练之分式2025-2026学年湘教版八年级上册
板块一:分式的乘除与乘方
1.计算:
(1)(2y)2.1xw:
02)2红.2x
xx+1
(3)2a-1÷a2-1
(4)x+3
片x2+3x
a2-4a+4a2-4
x2-2x
1(x-1)21
2.计算:
a2品
3.计算:
4.化简:
(0红.22)x8÷2+3x
xx+1
x2-2x+1(x-1)2
③》尝)2÷腊×层).4w2×24÷品4
4cd
a2-2a+1a+1
a2-1
板块二:分式的加减
1.计算a.3a-1
a-1a2-1
2.计算:
ab
、a-b
a-b
3.计算
(1)a-2.2a-3
(2)
1
(3)x2
-x-1.
a+1
a+1
x2-42x-4
x-1
4.计算:
(1)12a-1:
02)y+2-2型,(3)-22x3
3a3a
x-y x-y
x2-11-x2
板块三:分式混合运算
1.计算:
2.化简:
2yxY:②)8x)9取
x-y y-x
x2-2x+1
3化简:2228.21)2
a2-1a2-2a+1a-1
4.计算:
3x,4xx+2
(2)
m+2
m-1.m-4
(1)
2a2a2a
、m2-2mm2-4m+4m2
5.化简:
1)
a2-1a2-a
a2+2a+1a+1
2--y
2x x+y 2x"
板块四:分式化简求值
1.先化简,再求值:。,4a+20,其中a=亿-1八
a2
a2
2先化简,再求值:(11)÷21,其中x=3,
x-1”x2-2x+1
3先化商:再求价:。20-小
a2-a
其中a=-2
4.先化简,再求值:
6m+9).m2
m+
m
m+3,其中m满足m2+3m-2=0.
5先化简,再求值:(-2-11)÷(22-2,其中x是不等式组
x2-2x+11-x
x-1
[4(2x-1)≤3x+6
2x+1>x-1
的整数解.
2
4+4》
(1)化简A;
(2)请在-2,1,0,1中选择一个你喜欢的数作为x的值,并求A的值.
板块五:分式方程
1.解方程:
2x-1=3
x+1x+1
2.解方程:2红1=2.
x-1x2-1
3.解分式方程:,3
+2=1-x
4-xx-4
4.解方程:高--x+2=1
5.解分式方程:
)15
mm+3;
(2)x=2
-1r27+1.
【答案】
计算专练之分式2025-2026学年湘教版八年级上册
板块一:分式的乘除与乘方
1.计算:
(1)(2xy)2.1x:
2)2.2
2
xx+1
(3)2a1a21
(4)x+3
x2+3x
a2-4a+4a2-4
x2-2x+1(x-1)2
【答案】解:(1)(2xy)2.1y
2
=4xy2.Ixy
2
=2x7y3,
22z.2
+1
=x(x+1),2x
X
x+1
=2x:
3)281÷a2-1
a2-4a+4a2-4
=a-1
(a-2)(a+2)
(a-2)2(a-1)(a+1)
=a+2
(a-2)(a+1)
=a+2
a2-a-2
(4)x+3
x2+3x
x2-2x+1(x-1)2
x+3
.(x-1)2
(x-1)2x(x+3)
是
2.计算:
a{:@品
【案】①名@品
5
4v
【详解】(1)解:
j
-y3
y2 x3
4y2
4y
(2)解:
a
4a4)
a
25b25b
a2 25b2 a
b24a 5b
5
=Aab
3.计算:
(1)6a2b÷
a
2b46
2)-4x-2
x2+2x+1x+1
【答案】(1)6ab②)x+2
x+1
【详解】(1)解:6a2b÷-
(2b4b2
=6a'b+
a
4b24b7
=6a2b.
4b2 a
a24b2
=6ab;
(2)
x2-4.x-2
x2+2x+1x+1
_x+2x-2x-2
(x+1)
x+1
=x+2x-2x+1
(x+12
x-2
=+2
x+1
4.化简:
(10红,2.2)3÷2+3x
xx+l
x2-2x+1(x-1)2
(3)(驰)2÷3×(53).4,a2×24a4÷a2-4
2c
4cd
2d
a2-2a+1a+1a2-1
【答案】解:(1)+区.2x
xx+1
=x(x+1).2x
x+1
=2x:
(2)x+3
x2+3x
x2-2x+1
(x-1)2
=x+3
-.(x-1)2
(x-1)2x(x+3)
=1
2c
4cd
=a2b2.4cd,3
4c2
3ab2d
4),a2Xa24a4÷a2-4
a2-2a+1
a+1a2-1
=a+2。(a-2)2.(a+1)(a-1)
(a-1)2a+1(a+2)(a-2)
=a-2
a-1
板块二:分式的加减
1.计算a.3a-1
a-1a2-1
【答案】解:a3a-1
a-1a2-1
a(a+1)
3a-1
(a+1)(a-1)(a+1)(a-1)
(a-1)2
(a+1)(a-1)
=a-1
a+1
a2
2.计算:
ab
a-B-at
a-b
【答案】
2ab
a-b
【解析】解:
ab
a2
-a+
=ab_ala-b):ai__ab-ala-b)+a'_ab-a'tab+a_2ab
a-b
a-b a-b a-b a-b
a-b
a-b
a-b
3.计算
(1)a-2.2a-3
1
.2
(2)
a+1a+1
x2-42x-4
(3)
x-1.
x-1
【答案】解:(1)a-2-
2a-3
a+1
a+1
=(a-2)-(2a-3)
a+1
=-a+1
a+1
=-a-1
a*1
1
2x-4
2x
x+2
2(x2-4)
2(x2-4)
=2x-(x+2)
2(x2-4)
x-2
2(x+2)(x-2)
1
2(x+2)
(3)x2
211
=x2.(x+1)(x-1)
x-1
x-1
-x2-(x2-1)
x-1
=1
x-1
4.计算:
(1)12a-1」
02)y+2-2y,3)-22x3
3a 3a
x-y x-y
x2-11-x2
【答案】解:(1)原式=1+2a-1
3a
=2a
3a
2
(2)原式=y+x2-2xy
x-y
=x(x-y)
x-y
=X;
(3)原武-2-2,2x+3
x2-1x2-1
=x2+2x+1
(x+1)(x-1)
=
(x+1)2
(x+1)(x-1)
=x+1
x-1
板块三:分式混合运算
1.计算:
(1)a
a2
;(2
x-1
a-11-a
、2x-1x2-4x+4
【答案】(①)-a2)1
-2
【详解】(1)解:a+a己
a-11-a
a a2
a-1a-1
a-a2
a-1