Edexcel IGCSE Maths 复习笔记 2.6.1 Algebraic Fractions - Adding & Subtracting
What is an algebraic fraction?
- An algebraic fraction is simply a fraction with an algebraic expression on the top (numerator) and/or the bottom (denominator)
Adding & subtracting
- Rules same as numeric fractions:
- Find the lowest common bottom (denominator)
- Write fractions with new bottoms
- Multiply tops by the same as bottoms
- Write as a single fraction (take care if subtracting)
- Simplify the top
- Always leave your answer in as simple a form as possible (see Algebraic Fractions – Simplifying)
Leaving the top and bottom of the fraction in factorised form will help you see if anything cancels.