
Andrew M. answered 02/10/18
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
f(x)=(x-5)^2+3
Are you looking for the inverse of f(x)?
As in g(x) = f-1(x)
To find the inverse of a function...
1) replace f(x) with y
y = (x-5)2 + 3
2) switch y and x in the equation
x = (y-5)2 + 3
3) Solve for y
(y-5)2 = x - 3
y - 5 = ±√(x-3)
y = 5 ±√(x-3)
4) replace y with f-1(x)
f-1(x) = 5 ±√(x-3)
Given the duality of the square root, f-1(x) is not a function because
to be a function every input value, x, in the domain can have one and only one
output value y in the range.