f(x) = 2x + 3
To find the inverse, x and f(x) must be switched, and then solved for f(x)
f(x) = 2x + 3
x = 2*f(x) + 3
x - 3 = 2*f(x) + 3 - 3
x - 3 = 2*f(x)
(x-3)/2 = 2*f(x) / 2
(x-3)/2 = f(x)
The inverse of f(x) = 2x + 3 is f(x) = (x-3)/2
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