diket f(x)=(2x-3) dan g(x)=2x+5 tentukan [tex] {fog}^{ - 1} (2)[/tex] [tex] {gof}^{ - 1} ( - 1)[/tex] [tex] {gog}^{ - 1} ( - 1)[/tex]

Cari fog (x) lalu di inverskan dan masukan x yang tanyakan

nomor 1
(fog) (x) = 2(2x + 5) - 3
(fog) (x) = 4x + 10 - 3
(fog) (x) = 4x + 7
y = 4x + 7
4x = y - 7
x = (y - 7) /4
(fog)-¹ (x) = (x - 7) / 4

(fog)-¹ (2) = (2 - 7) / 4
= - 5/4

nomor 2
(gof) (x) = 2(2x - 3) + 5
(gof) (x) = 4x - 6 + 5
(gof) (x) = 4x - 1
y = 4x - 1
4x = y + 1
x = (y + 1) / 4
(gof)-¹ (x) = (x + 1) / 4

(gof) -¹(-1) = (-1 + 1) / 4
= 0

nomor 3
(gog) (x) = 2(2x + 5) + 5
(gog) (x) = 4x + 10 + 5
(gog) (x) = 4x + 15
y = 4x + 15
4x = y - 15
x = (y - 15) / 4
(gog) -¹ (x) = (x - 15) / 4

(gog)-¹ (-1) = (-1 - 15) / 4
= -16/4 = -4