Diketahui = f(x) = {(1,4) , (2,5), (3,7) } g(x) = { (4,-1),(5,-2),(7,-3)} Maka ( g o f ) pangkat -1 =

jawab

f(x)= (1,4), (2,5), (3,7)
g(x)= (4,-1),(5,-2),(7,-3)

gof (x) = g { f(x)}
f(1) = 4  → g(4) = -1  
f(2) = 5 → g (5) = -2
f(3) = 7 → g(7) = -3

gof(x) = (1, -1), (2, -2), (3, -3)
maka
(gof)⁻¹ (x)= (-1, 1), (-2, 2), (-3 , 3)