Multiplying and Dividing Rational Expressions 5.2 Multiplying and Dividing Rational Expressions

Multiplying Rational Expressions If are rational expressions, then To multiply rational expressions, multiply the numerators and then multiply the denominators.

Multiplying Rational Expressions After multiplying such expressions, our result may not be in simplified form, so we use the following techniques. To Multiply Rational Expressions Step 1: Completely factor numerators and denominators. Step 2: Multiply numerators and multiply denominators. Step 3: Simplify or write the product in lowest terms by dividing out common factors.

Multiplying Rational Expressions Example 6x2 5x Multiply: • 10x3 12

Multiplying Rational Expressions Example (m – n)2 m Multiply: • m + n m 2 – mn

Dividing Rational Expressions If are rational expressions, then To divide two rational expressions, multiply the first rational expression by the reciprocal of the second rational expression.

Helpful Hint Remember, to Divide by a Rational Expression, multiply by its reciprocal.

Dividing Rational Expressions Example Divide:

Units of Measure Converting Between Units of Measure Use unit fractions (equivalent to 1), but with different measurements in the numerator and denominator. Multiply the unit fractions like rational expressions, canceling common units in the numerators and denominators.

Units of Measure 1008 square inches = _________ square feet. Example 1008 square inches = _________ square feet. (1008 sq in) (2·2·2·2·3·3·7 in · in)