Answer:
f^-1(x) = -4 / x - 2
Explanation:
First swap the x and y values. This is done by setting f(x) to x, and x to y.
f(x) = (2x - 4) / x → x = (2y - 4) / y
*Then solve for y like you would for a normal equation*
x = (2y - 4) / y
×y ×y
(multiplication property of equality)
*This will isolate the extra y term*
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xy = 2y - 4
-2y -2y
(subtraction property of equality)
*This is done to group the like terms together, because they both share a y term now*
_____________________________
xy - 2y = -4
| |
v v
( x - 2 )
(GCF)
*In this case the GCF is y because it is the factor held in common, reverse distributive property*
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y(x-2) = -4
÷(x-2) ÷(x-2)
(Division property of equality)
*This is the last and final step to isolate the y term completely, so we can find the inverse*
y = -4/x-2
*This is the inverse*
Now just set it in function form as an inverse:
y = -4/x-2 → f^-1(x) = -4/x-2