Question

function f(X) =(1/x) -2 is one to one
find the inverse

Answer 1

y = 1/x - 2
multiply by x:
yx = 1 - 2x
yx+2x = 1
x(y+2) = 1
x = 1/(y+2)

f^-1(x) = 1/(x+2).

Answer 2

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