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Help answer all please wrong answers will get reported

Help answer all please wrong answers will get reported-example-1
User MarkOfHall
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1 Answer

8 votes

If
f^(-1)(x) is the inverse of
f(x), then by definition of inverse functions,


\left(f\circ f^(-1)\right)(x) = f\left(f^(-1)(x)\right) = x

Given
f(x) = 2x-8, the inverse, if its exists, satisfies the equation above. Evaluate
f at the inverse, we have


f\left(f^(-1)(x)\right) = 2 f^(-1)(x) - 8 = x

Solve for the inverse:


2 f^(-1)(x) - 8 = x


2 f^(-1)(x) = x + 8


\boxed{f^(-1)(x) = \frac12 x + 4}

Given
g(x) = \frac13 x + 5, we do the same thing as before to find its inverse.


g\left(g^(-1)(x)\right) = \frac13 g^(-1)(x) + 5 = x \implies \boxed{g^(-1)(x) = 3x - 15}

User Aska
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