Summary: Lecture 5.
Addition and subtraction of rational expressions
Two rational expressions in general have different denominators, therefore if you want to
add or subtract them you need to equate the denominators first. The common denominator
with the smallest possible degree is the Least Common Multiple of the original ones. On this
lecture we will consider the procedure of finding the Least Common Multiple and solve some
examples on addition and subtraction of rational expressions.
5.1. Addition and subtraction of rational expressions
The rules for adding and subtracting rational expressions are the same as rules for
adding and subtracting fractions.
a + c