3-m^2=- 1,m= 2

m+ 1≠0，m≠- 1

So, y=3/x, or y =-1/x.

When y=3/x

a=3/(√2- 1)=3(√2+ 1)

When y=- 1/x

a =- 1/(√2- 1)=-(√2+ 1)