f(x)= 2x+5 g(x) = 2x-6x+5 ditanyakan gof(x), fog(x), f(x),g(x),f^¹og^1(x),g^¹o f^1(x)

Jawabannya :
Matematika....

Cari dulu f^-1(x) dan g^-1(x) :
f(x) = 2x+5
y = 2x+5
-2x = -y+5
------------------- dikalikan -1
2x = y-5
x = y-2/5
f^-1(x) = x-2/5

g(x) = 2x-6x+5
y = 2x-6x+5
-2x+6x = -y+5
----------------------- dikalikan -1
2x-6x = y-5
x(2-6) = y-5
x = y-5/2-6
x = y-5/-4
g^-1(x) = x-5/-4

gof(x) = g[f(x)]
= g[2x+5]
= 2(2x+5)-6(2x+5)+5
= 4x+10-12x-30+5
=-8x-15

fog(x) = f[g(x)]
= f[2x-6+5]
= 2(2x-6+5)+5
= 4x-12+10+5
= 4x+3