Question

分式方程求解！！！！！

先化简，再求值：2/x+1－x-3/x²-1，其中x=2013。

Answer 1

2/x+1－x-3/x²-1=2／（x+1)－(x－3)／(x+1)（x－1)
通分得化简得1／（x－1)，∵x=2013,∴原式=1／2012

Answer 2

2/（x+1）－（x-3）/（x²-1）=[2(x-1)-x+3]/(x²-1)=1/(x-1)

当x=2013时 1/(x-1)=1/2012

Answer 3

原式=2/(x+1)-{(x-1)-2}/(x+1)(x-1)
=2/(x+1)-1/(x+1)+2/(x+1)(x-1)
=1/(x+1){1+2/(x-1)}
=1/(x+1){(x-1+2)/(x-1)}
=1/(x-1)
=1/2012

Answer 4

2/(x+1)－(x-3)/(x²-1)

=[2(x-1)－(x-3)]/(x²-1)
=(x+1)/(x²-1)
=1/(x-1)
=1/2012