If f (x) = 2x - 4, find f-1 (x)

Answer

f-1 (x) = (x+4) / 2

Step-by-step explanation:

given f (x) = 2x - 4

let y = f (x) and rearrange to express x in terms of y

y = 2x - 4 (add 4 to each side)

y + 4 = 2x (divide both sides by 2)

(y+4) / 2 = x (rearrange)

x = (y+4) / 2

f-1 (y) = (y+4) / 2

hence

f-1 (x) = (x+4) / 2