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Help pls!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Help pls!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!-example-1

1 Answer

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Answer:

See below.

Explanation:

a.


f(x) = (x + 12)/(x - 4)


y = (x + 12)/(x - 4)


x = (y + 12)/(y - 4)


x(y - 4) = y + 12


xy - 4x - y = 12


y(x - 1) = 4x + 12


y = (4x + 12)/(x - 1)


f^(-1)(x) = (4x + 12)/(x - 1)

b.


f(f^(-1)(x)) =


= ((4x + 12)/(x - 1) + 12)/((4x + 12)/(x - 1) - 4) =


= (((4x + 12)/(x - 1) + 12)(x - 1))/(((4x + 12)/(x - 1) - 4)(x - 1))


= (4x + 12 + 12x - 12)/(4x + 12 - 4x + 4)


= (16x)/(16)


= x


f^(-1)(f(x)) =


= (4((x + 12)/(x - 4)) + 12)/((x + 12)/(x - 4) - 1)


=([4((x + 12)/(x - 4)) + 12](x - 4))/(((x + 12)/(x - 4) - 1)(x - 4))


=(4x + 48 + 12x - 48)/(x + 12 - x + 4)


= (16x)/(16)


= x

User Andy Jacobs
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