Respuesta :
The inverse of the function f(x)=(2x-4)^2 for x≥2 is g(x) = (√x)/2 + 2 (for x ≥ 0)
What is inverse of a function?
Suppose that the given function is
[tex]f:X\rightarrow Y[/tex]
Then, if function 'f' is one-to-one and onto function (a needed condition for inverses to exist), then, the inverse of the considered function is
[tex]f^{-1}: Y \rightarrow X[/tex]
such that:
[tex]\forall \: x \in X : f(x) \in Y, \exists \: y \in Y : f^{-1}(y) \in X[/tex]
(and vice versa).
It simply means, inverse of 'f' is undo operator, that takes back the effect of 'f'
For this case, the given function is:
[tex]f(x)=(2x-4)^2 \: \: \: (\text{for }x \geq 2)[/tex]
Take y = f(x).
Expressing x (which is input to f(x) ) in terms of y (which is output f(x) ) as:
[tex]y = (2x-4)^2\\\text{Taking positive sq. root}\\\\\sqrt{y} = (2x-4)[/tex]
(we could legally take positive root since 2x - 4 ≥ 0 because of x ≥ 2 (if 2x - 4 wouldn't be ≥ 0, then as √y ≥0, we would have to write [tex]\pm \sqrt{y} = (2x-4)[/tex] )
Proceeding further:
[tex]\sqrt{y} = (2x-4)\\\\x = \dfrac{\sqrt{y} + 4}{2}[/tex] = g(y)
(this 'g' is the inverse function of y = f(x) )
The g(y) has its own existance, so better not relate it depending on y = f(x).
Since we usually symbolize inputs by variable x, so we get:
[tex]g(x) = \dfrac{\sqrt{x} + 4}{2} = \dfrac{\sqrt{x}}{2} + 2[/tex]
This is defined only if x ≥ 0 (because sq. root isn't defined for negative values, (if working with real numbers only) ).
Thus, the inverse of the function [tex]f(x)=(2x-4)^2[/tex] for x≥2 is [tex]g(x) = \dfrac{\sqrt{x}}{2} + 2, \text{(for x } \geq 0)[/tex]
Learn more about inverse function here:
https://brainly.com/question/19425567