Diketahui f(x)=(x+1)(x-1) hitung nilai f¹(-1)

fx= x^2-x+x-1
fx= x^2-1
fx^-1= x^2-1
y= x^2-1
-x^2= -y-1 (dikali minus)
x^2= y+1
[tex]x = + - \sqrt{y + 1} \\ fx = + - \sqrt{x + 1} [/tex]