Addition and subtraction of algebraic fractions

Addition and Subtraction of Algebraic Fractions

Understanding the Basics

  • An algebraic fraction is a fraction where the numerator and/or the denominator are algebraic expressions.

  • Algebraic fractions can be added or subtracted just like numerical fractions. However, they have to have a common denominator to simplify or perform additional mathematical operations.

Key Characteristics

  • Algebraic fractions often contain variables in the numerator, denominator, or both.

  • The primary characteristic of addition and subtraction of algebraic fractions involves applying the principles of rational numbers to algebraic expressions.

  • Before conducting addition or subtraction, ensure that the fractions have the same denominator. This is a result of the fundamental rule of fractions that only likewise terms can be directly added or subtracted.

Pointers for Solving these Fractions

  1. Determine the lowest common denominator (LCD) of the algebraic fractions involved.

  2. Convert all fractions so they each have the LCD.

  3. You may then add or subtract the fractions, summing or subtracting the numerators, while the denominator, the LCD, remains the same.

  4. Finally, simplify the resulting algebraic fraction, if necessary.

Example Illustrations

  • To illustrate: if you were to add (2/x) + (3/y), first identify the LCD, which in this case is xy. Rewrite the fractions as (2y/xy) + (3x/xy). The resulting fraction is (2y + 3x)/xy.

  • Another example: to subtract (5/a) - (4/b), determine the LCD, which is ab. Rewrite the first fraction as (5b/ab) and the second one as (4a/ab). The resulting fraction is (5b - 4a)/ab.

In Conclusion

  • To add or subtract algebraic fractions ensure they have a common denominator.

  • To find the common denominator, you may have to multiply or manipulate the original fractions.

  • It’s crucial to be proficient with these operations as they form the core of handling and solving more complex algebraic expressions. Remember to simplify your final answer.