Diketahui f (x)=2x²-1 dan (fog) (x)=2x²+12x+17, maka g (x)=…

Diketahui f (x)=2x²-1 dan (fog) (x)=2x²+12x+17, maka g (x)=…
A. X-3
B. X+3
C. X-2
D. X+2
E. X+1

jawaban untuk pertanyaan diatas adalah B. x + 3

Konsep
(fog) (x) = f(g(x))

ab + cb = (a+c). b

Diketahui
f (x)=2x²-1 dan
(fog) (x)=2x²+12x+17,
maka g (x)=…

(fog) (x) = 2x²+12x+17
f(g(x)) = 2x²+12x+17
2g(x)² – 1 = 2x²+12x+17
2 g(x)² = 2x²+12x+17 + 1
2 g(x)² = 2x²+12x+18
Kedua ruas dibagi 2 menjadi
g(x)² = x² + 6x + 9
g(x)² = x² + 3x + 3x +9
g(x)² = x(x+3) + 3(x+3)
g(x)²= (x+3)(x+3)
g(x)² = (x+3)²
g(x) = x+3

Jadi jawabnya adalah B. x + 3

Baca Juga :  Complete the sentences with a form of the verb in parentheses. Three hundred and fifty years ago, people (1. make) /made/ their own clothes. They (2. have, not) _____ machines for making clothes. There (3. be, not) _____ any clothing factories. People (4. tear) _____ homemade clothes that were sewn by hand. Today, very few people (5. make) _____ their own clothes. Clothing (6. come) _____ ready-made from factories. People (7. buy) _____ almost all their clothes from stores. The modern clothing industry (8. be) _____ international. As a result, people from different countries often (9. wear) _____ similar clothes. For example, people in many different countries throughout the world (10. wear) _____ jeans and t-shirts. However, some regional differences in clothing still (11. exist) _____ for instance, people of the Arabian deserts (12. wear) _____ loose, flowing lobes to protect themselves from the heat of the sun. In parts of Northern Europe, fur hats (13. be) _____ common in the winter. In the future, there (14. be, probably) _____ fewer and fewer differences in clothing. People throughout the world (15. wear) _____ clothes from the same factories. (16. We all, dress) _____ in the future? TV shows and movies about the future often (17. show) _____ everybody in a uniform of some kind. What (18. you, think) _____? Number 10