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Let f(x) = 2x + 2. Solve f−1(x) when x = 4. (1 point)

User Ben Hirschberg
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2 Answers

11 votes
11 votes

If f(x) = 2x + 2 is invertible, then its inverse is another function f ⁻¹(x) such that

f(f ⁻¹(x)) = 2 f ⁻¹(x) + 2 = x

Solve for f ⁻¹(x) :

2 f ⁻¹(x) + 2 = x

2 f ⁻¹(x) = x - 2

f ⁻¹(x) = (x - 2)/2 = x/2 - 1

Then when x = 4, we have f ⁻¹ (4) = 4/2 - 1 = 2 - 1 = 1.

User ZviBar
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18 votes
18 votes

Answer:

1

Explanation:

First, find the inverse of the original function.

x = 2y + 2

x-2/2

Second, substitute x with 4 and solve.

4-2/2

2/2

1

Best of Luck!

User Nidhin
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