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If fx = 3x over 5 +3 which of the following is the inverse

1 Answer

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Answer:

f^(-1)(x) = -3x/(3x-3)

Explanation:

1) replace f(x) by y

● y = 3x/(5x+3)

2) exchange x and y

● y = 3x/(5x+3)

● x = 3y / (3y +3)

3) solve for y

● x = 3y / (3y +3)

● x (3y +3) = 3y

● 3xy + 3x = 3y

● 3xy - 3y = -3x

● y (3x - 3) = -3x

● y = -3x /(3x-3)

4) replace y with f^(-1)(x)

● y = -3x/(3x-3)

● f^(-1)(x) = -3x/(3x-3)

User Kingsley Ijike
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