Question

已知函数f(x)=

x-1

1+x

，那么f(

2

)=______．

Answer 1

∵f(x)=

x-1

1+x

，
∴f(

2

)=

2 -1

1+ 2

=

( 2 -1)( 2 -1)

(1+ 2 )( 2 -1)

=3-2

2

．
故答案为3-2

2

．