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F(x)=x-4/x-8. find f composed f of x.

User Serdia
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1 Answer

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Answer: (-3x + 28)/(24 - 7x).

Step-by-step explanation: To find f composed with f of x, we need to substitute the expression f(x) into itself and simplify.

Given:

f(x) = (x - 4)/(x - 8)

1. Substitute f(x) into itself:

f(f(x)) = f((x - 4)/(x - 8))

2. Simplify the expression:

To simplify, we substitute the expression (x - 4)/(x - 8) into f(x).

f(f(x)) = [(x - 4)/(x - 8) - 4]/[(x - 4)/(x - 8) - 8]

3. Simplify further:

To simplify this expression, we need to find a common denominator for both fractions.

f(f(x)) = [(x - 4 - 4(x - 8))/(x - 8)] / [(x - 4 - 8(x - 4))/(x - 8)]

Expanding the numerator and denominator:

f(f(x)) = [(x - 4 - 4x + 32)/(x - 8)] / [(x - 4 - 8x + 32)/(x - 8)]

Simplifying the numerator and denominator:

f(f(x)) = [(-3x + 28)/(x - 8)] / [(24 - 7x)/(x - 8)]

4. Divide the fractions:

To divide two fractions, we multiply the first fraction by the reciprocal of the second fraction.

f(f(x)) = [(-3x + 28)/(x - 8)] * [(x - 8)/(24 - 7x)]

Cancelling out the common factor (x - 8):

f(f(x)) = (-3x + 28)/(24 - 7x)

Therefore, f composed with f of x is given by the expression (-3x + 28)/(24 - 7x).

SEEE :)

User Jessems
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