问题 解答题
(1)计算:
x2
y-x
-
y2
y-x
(2)解方程:
1
x-3
=2+
x
3-x
答案

(1)计算:

x2
y-x
-
y2
y-x
=
x2-y2
y-x
=
(x-y)(x+y)
y-x
=-(x+y);

(2)解方程:

1
x-3
=2+
x
3-x

两边同时乘x-3得,1=2(x-3)-x,

化简得,1=2x-6-x,

解得x=7.

检验:当x=7时,x-3≠0,故x=7是原分式方程的解.

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