Try Out 3 Matematika IPA 2019 no 1

Try Out Matematika IPA 2019
Soal dan Pembahasan Try Out Matematika IPA 2019
Jawaban Try Out Matematika IPA 2019
Try Out Ujian Matematika SMA IPA

1. Jika diketahui fungsi f(x) = 2x - 6, f : R → R dan (g o f) (x) = 6x - 14 maka g^-1(10)= ...

A. -26
B. -2
C. 2
D. 26
E. 34



Jawaban : C

f(x) = 2x - 6
y = 2x - 6
2x = y + 6
x = 1/2 y + 3

g ( f(x) ) = 6x - 14

g(x) = 6 (1/2 y + 3) - 14
g(x) = 3y + 18 - 14
g(x) = 3y + 4

g(x) = 3x + 4
y = 3x + 4
3x = y - 4
x = 1/3y - 4/3

g^-1(x) = 1/3 x - 4/3
g^-1(10) = 10/3 - 4/3 = 2

>> Nomor 2