Help with a inverse function?

Question

Find the inverse of f(x)= x ^2 + 2x-1, x>0

Answer 1

given  y= x ^2 + 2x-1

inverse is  x= y ^2 + 2y-1

solve for y

y ^2 + 2y=x+1

y ^2 + 2y+1=x+1+1

(y+1)(y+1)=x+2

y+1=sqrt (x+2)

y=sqrt(x+2)-1

Answer 2

y=x ^2 + 2x-1

x=y ^2 + 2y-1

x+1=y ^2 + 2y

x+1=y(y+2)

y=(x+1)/(y+2)