tolong jawab nomor 9 gan trmksh pake cara ya...

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

Atau

f(x) = 1/(x + 2)
y = 1/(x + 2)
xy + 2y = 1
xy = 1 - 2y
x = (1 - 2y)/y
f^-1(x) = (1 - 2x)/x
-4 = (1 - 2x)/x
-4x = 1 - 2x
-2x = 1
x = -1/2