Question

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

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4
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Answer 1

Assuming that is inverse, this question is asking what x will give an answer of 4 in the original function.

Answer 2

first you have to find inverse of f(x) and then substitute x for 4 \[f(x) = 2x+2\]
f(x) is same as y
so we can rewrite it
\[y = 2x+2\]
to find inverse Switch the x and y
\[x = 2y+2\]
1st) solve for y
2nd) replace x with 4
3rd) simplify and that would be the answer