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2 votes
If f (x) = 3x - 2 and fog(x) = 6x - 2 then find the value of
x such that gof(x) = 8.​

User Derron
by
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1 Answer

5 votes

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Answer:

x = 2

Explanation:

To find g(x), we can start with the inverse of f(x).

f(y) = x . . . . . . . solve this to find f^-1(x)

3y -2 = x

3y = x +2 . . . . add 2

y = (x +2)/3 = f^-1(x) . . . . divide by 3

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Now, we can find g(x):

f^-1(f(g(x)) = g(x)

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

6x/3 = g(x) = 2x

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Now, we want g(f(x)) = 8

g(3x -2) = 8

2(3x -2) = 8

6x -4 = 8

6x = 12

x = 2 . . . . makes g(f(x)) = 8

User Loose
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