Adding and Subtracting Rational Expressions with Unlike Denominators There are a few steps to follow when you add or subtract rational expressions with unlike denominators.
To add/subtract rational expressions with the same denominator. 1. Add/subtract the numerators. Write this sum/difference as the numerator over the common denominator.
1) Make the denominators of the rational expressions the same by finding the Least Common Denominator (LCD). Note: The Least Common Denominator is the same as the Least Common Multiple (LCM) of the given denominators. 2) Next, combine the numerators by the indicated operations (add and/or subtract) then copy the common denominator.
Uses worked examples to demonstrate the steps involved in adding rational expressions. Warns against common mistakes.
This online calculator performs addition and subtraction of algebraic fractions.
Intro to adding rational expression with unlike denominators (2 min) Adding rational expressions: unlike denominators (5 min) Subtracting rational expressions: unlike denominators (5 min) Least common multiple (4 min) Least common multiple: repeating factors (2 min) Subtracting rational expressions: factored denominators (4 min)
