Algebraic Fractions
Understanding Algebraic Fractions
- Algebraic fractions are fractions where the numerator and/or the denominator are algebraic expressions.
- Like ordinary fractions, they follow the same rules for addition, subtraction, multiplication, and division.
Simplifying Algebraic Fractions
- An algebraic fraction is in its simplest form when the greatest common divisor (GCD) of its numerator and denominator is 1.
- To simplify an algebraic fraction, factorise the numerator and the denominator and then cancel out common factors.
- Be careful with minus signs and double-check your work.
Adding and Subtracting Algebraic Fractions
- Like normal fractions, to add or subtract algebraic fractions, they must have a common denominator.
- A common denominator is the least common multiple (LCM) of the two denominators.
- Once the denominators are the same, add or subtract the numerators and simplify if possible.
Multiplying Algebraic Fractions
- When multiplying algebraic fractions, multiply the numerators together to create a new numerator, and then do the same for the denominators.
- Simplify the fraction if possible.
Dividing Algebraic Fractions
- To divide algebraic fractions, multiply the first fraction by the reciprocal of the second fraction.
- Remember, the reciprocal of a fraction is obtained by switching the numerator and the denominator.
- Simplify the resulting fraction, if necessary.
Solving Equations Involving Algebraic Fractions
- To solve an equation involving algebraic fractions, first try to clear the fractions.
- Clearing the fractions usually involves multiplying through by a common denominator.
- This will often turn the equation into a simple linear or quadratic equation that can be solved using standard techniques.
Remember: Always simplify your final answer, if possible. Most importantly, practise plenty of example problems to master these techniques.