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Adding and subtracting rational expressions
Learn how to add and subtract rational expressions. Like multiplication and division, this skill has a remarkable affinity to adding and subtracting fractions!
Ease into the realm of rational-expression-addition-and-subtraction by first working with expressions that have the same denominator.
Sal rewrites a/b+c/d as a single rational expression.
Add and subtract rational expressions with relatively prime denominators by manipulating them to have the same denominators.
Sal finds the lcm (least common multiple) of 12 and 36, and of 12 and 18. He shows how to do that using the prime factorization method, which is a just great!
Sal finds the lcm (least common multiple) of 25 and 30.
Find the lcm (least common multiple) of pairs of integers.
Add and subtract rational expressions with factored denominators by manipulating them to have the same denominators.
Sal performs the following subtraction and simplifies the result: (a-2)/(a+2) - (a-3)/(a^2+4a+4).
Master the skill of rational-expression-addition-and-subtraction by working with expressions whose denominators aren't factored and may or may not have shared factors.