Year 11 - Maths
Changing the subject with multiple algebraic fractions
Algebraic fractions
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This pupil-friendly study guide includes a unit summary, clear notes, common mistakes, and quick questions with answers.
Unit Summary
In this unit, pupils apply skills in manupulating and solving various equations and formulae to algebraic fractions in order to change the subject and manipulate them.
Lesson Summary
You will learn to change the subject of a formula involving multiple algebraic fractions.
Key Notes
- It is important to identify which variable is to become the subject.
- Like terms containing the new subject should be collected.
- You should be prepared to utilise any of your algebraic manipulation skills.
Vocabulary To Learn
- Subject of an equation/formula: The subject of an equation/a formula is a variable that is expressed in terms of other variables. It should have an exponent of 1 and a coefficient of 1
Common Mistakes To Avoid
- Pupils may think that the reciprocal of $$\\frac{1}{a} + \\frac{1}{b}$$ is $$a + b$$
3 Quick Questions (With Answers)
1. Solve this in steps: explain the method from this lesson and why each step matters.
It is important to identify which variable is to become the subject. Like terms containing the new subject should be collected.
2. Use this key word in a maths sentence and explain it clearly. 'Subject of an equation/formula'
The subject of an equation/a formula is a variable that is expressed in terms of other variables. It should have an exponent of 1 and a coefficient of 1. Use this word when showing your method, then check your final answer is reasonable.
3. Spot and fix this common maths mistake.
Mistake: Pupils may think that the reciprocal of $$\\frac{1}{a} + \\frac{1}{b}$$ is $$a + b$$. Correction: $$\\frac{1}{2} + \\frac{1}{4} = \\frac{3}{4}$$ which is not the reciprocal of 2 + 4 = 6. To find the reciprocal, it helps for the expression to be written as a single fraction.
More Lessons In This Unit
- Changing the subject where the variable appears in multiple terms Study Guide
- Checking and securing understanding of changing the subject with simple algebraic fractions Study Guide
- Checking and securing understanding of solving with simple algebraic fractions Study Guide
- Operations with algebraic fractions Study Guide
- Problem solving with advanced algebraic fractions Study Guide
- Simplifying algebraic fractions Study Guide
- Solving equations with algebraic fractions Study Guide
Browse all guides in the Year 11 Maths guide library.