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If f (x) = 1/9x - 2, what is f^1(x)?

a) f^1 (x) = 1/9x-2
b) f^1(x)=1/9x+2
c) f^1=9x+2
d) f^1 (x)= -2x+ 1/9

User Joe Eigi
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1 Answer

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Final answer:

The correct expression for the inverse function f^(-1)(x) of f(x) = 1/9x - 2 is f^(-1)(x) = 9x + 2, which corresponds to option c).

Step-by-step explanation:

To find the inverse function f^(-1)(x) of f(x) = 1/9x - 2, begin by setting f(x) equal to y. Then, interchange x and y to solve for y in terms of x. The original function equation is y = 1/9x - 2.

Swap x and y to get x = 1/9y - 2. To isolate y, add 2 to both sides: x + 2 = 1/9y. Multiply both sides by 9 to solve for y, obtaining 9x + 18 = y, or y = 9x + 18. Simplifying by subtracting 18 from both sides yields the inverse function f^(-1)(x) = 9x + 2.

The process of finding an inverse function involves interchanging x and y in the original function equation, solving for y, and then re-expressing the equation solved for y in terms of x to obtain the inverse function. In this case, f^(-1)(x) = 9x + 2 reflects the correct inverse function of f(x) = 1/9x - 2, aligning with option c). Therefore, the accurate representation of the inverse function is f^(-1)(x) = 9x + 2 among the provided options.

User Paul Stone
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