Diketahui fungsi f(x)=x^2-2x+3,g(x)=2x-1 tentukan
C)g•f(-1)
D)f•g(-2)
C)g•f(-1)
D)f•g(-2)
Jawab:
Jawaban terlampir
C)
gof(x) = g(f(x))
= 2.(x²-2x+3) - 1
= 2x²-4x+6-1
= 2x²- 4x + 5
Sehingga,
gof(-1) = g(f(-1))
= 2(-1)² - 4(-1) + 5
= 2 + 4 + 5
=11
D)
fog(x) = f(g(x))
= (2x-1)² - 2(2x-1) + 3
= 4x²-4x-1 - 4x +2 + 3
= 4x² - 8x +4
Sehingga
fog(-2) = f(g(-2))
= 4(-2)² - 8(-2) + 4
= 16 + 16 + 4
=36
Semoga membantu, ya.