Multiplying and Dividing Rational Expressions Math Example 4

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Example 4

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Divide x+5xโˆ’1รทx+5x2โˆ’1\frac{x + 5}{x - 1} \div \frac{x + 5}{x^2 - 1}.

Solution

  1. 1
    Flip: x+5xโˆ’1โ‹…x2โˆ’1x+5=x+5xโˆ’1โ‹…(x+1)(xโˆ’1)x+5\frac{x+5}{x-1} \cdot \frac{x^2 - 1}{x+5} = \frac{x+5}{x-1} \cdot \frac{(x+1)(x-1)}{x+5}.
  2. 2
    Cancel: x+1x + 1.

Answer

x+1x + 1, xโ‰ 1,โˆ’1,โˆ’5x \neq 1, -1, -5
After flipping the divisor, the (x+5)(x+5) and (xโˆ’1)(x-1) factors cancel. The restrictions come from all original denominators and the divisor's numerator.

About Multiplying and Dividing Rational Expressions

Multiplying rational expressions by multiplying numerators together and denominators together (after factoring and canceling). Dividing by multiplying by the reciprocal of the divisor.

Learn more about Multiplying and Dividing Rational Expressions โ†’

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