Example

Example of Dividing the Rational Functions f(x)=2x2x28xf(x) = \frac{2x^2}{x^2 - 8x} and g(x)=8x2+24xx2+x6g(x) = \frac{8x^2 + 24x}{x^2 + x - 6}

To find the quotient R(x)=f(x)g(x)R(x) = \frac{f(x)}{g(x)} for the rational functions f(x)=2x2x28xf(x) = \frac{2x^2}{x^2 - 8x} and g(x)=8x2+24xx2+x6g(x) = \frac{8x^2 + 24x}{x^2 + x - 6}, apply the procedure for dividing rational expressions:

Step 1. Substitute the polynomial expressions for f(x)f(x) and g(x)g(x): R(x)=2x2x28x8x2+24xx2+x6R(x) = \frac{\frac{2x^2}{x^2 - 8x}}{\frac{8x^2 + 24x}{x^2 + x - 6}}

Step 2. Convert the division to multiplication by taking the reciprocal of g(x)g(x): R(x)=2x2x28xx2+x68x2+24xR(x) = \frac{2x^2}{x^2 - 8x} \cdot \frac{x^2 + x - 6}{8x^2 + 24x}

Step 3. Factor the numerators and denominators completely, then multiply: R(x)=2x2(x+3)(x2)x(x8)8x(x+3)R(x) = \frac{2x^2(x + 3)(x - 2)}{x(x - 8) \cdot 8x(x + 3)}

Expanding the numerical factors to reveal all common parts: R(x)=2xx(x+3)(x2)x(x8)24x(x+3)R(x) = \frac{2 \cdot x \cdot x \cdot (x + 3)(x - 2)}{x(x - 8) \cdot 2 \cdot 4 \cdot x \cdot (x + 3)}

Step 4. Simplify by dividing out the common factors of 22, xx, xx, and (x+3)(x + 3): R(x)=x24(x8)R(x) = \frac{x - 2}{4(x - 8)}

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Updated 2026-04-30

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