Question

if f(x) = -2x + 4, then f^-1(x) =

Answer 1

Answer:

$f^{-1}(x) = -\frac{x}{2} +2$

Step-by-step explanation:

Consider the real number y such that  f ⁻¹(x) = y

$f^{-1}\left( x\right) =y\Longleftrightarrow f\left( y\right) =x$

We need to find y in order to determine the expression of  f ⁻¹(x)

f(y) = x ⇔ -2y + 4 = x

⇔ 4 - x = 2y

⇔ y = (4 - x)/2

$\Longleftrightarrow y=-\frac{x}{2} +2$