What is the answer out of the options in the image?
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Answer:
(fog)(x) = [tex] x [/tex]
Step-by-step explanation:
Given:
[tex] f(x) = \frac{x - 1}{3} [/tex]
[tex] g(x) = 3x + 1 [/tex]
Required:
(fog)(x)
SOLUTION:
(fog)(x) = f(g(x))
Substitute 3x + 1 into [tex] f(x) = \frac{x - 1}{3} [/tex]
f(g(x)) = [tex] \frac{(3x + 1)- 1}{3} [/tex]
[tex] = \frac{3x + 1 - 1}{3} [/tex]
[tex] = \frac{3x}{3} [/tex]
[tex] = \frac{x}{1} [/tex]
(fog)(x) = [tex] x [/tex]