MA01-06 Maths Watch
Inverse operations
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In this lesson
In this video you'll learn about inverse operations for GCSE Maths, with worked examples and the mistakes examiners report. By the end you'll be able to reverse a multi-step calculation by applying the correct inverse operation to every step, in the reverse order, to find an unknown starting value.
What it covers
- 0:49 Inverse operations: one step first
- 2:56 Two steps now
- 4:59 Worked example: inverse operations
- 7:13 Worked example: the next chain carries a minus sign
- 9:26 Common mistakes: inverse operations
- 11:14 Your turn: a short one, to find out whether this has
- 13:44 What's next
Key words
For: Cambridge IGCSE 0580, OCR GCSE J560, AQA GCSE 8300, Edexcel GCSE 1MA1, Eduqas GCSE C300
On the specification
| Board | Spec | Statement |
|---|---|---|
| Cambridge IGCSE 0580 | C1.6 | Use the four operations for calculations with integers, fractions and decimals, including correct ordering of operations and use of brackets. |
| Cambridge IGCSE 0580 | E1.6 | Use the four operations for calculations with integers, fractions and decimals, including correct ordering of operations and use of brackets. |
| OCR GCSE J560 | 1.03a | Know the conventional order for performing calculations involving brackets, four rules and powers, roots and reciprocals. |
| OCR GCSE J560 | 1.04a | Know that addition and subtraction, multiplication and division, and powers and roots, are inverse operations and use this to simplify and check calculations, for example, in reversing arithmetic in "I'm thinking of a number" or "missing digit" problems. |
| AQA GCSE 8300 | N3 | Recognise and use relationships between operations, including inverse operations (eg cancellation to simplify calculations and expressions) |
| Edexcel GCSE 1MA1 | N3 | Recognise and use relationships between operations, including inverse operations (e.g. cancellation to simplify calculations and expressions); use conventional notation for priority of operations, including brackets, powers, roots and reciprocals |
| Eduqas GCSE C300 | FN3 | Recognise and use relationships between operations, including inverse operations (e.g. cancellation to simplify calculations and expressions; use conventional notation for priority of operations, including brackets, powers, roots and reciprocals) |
| Eduqas GCSE C300 | HN3 | Recognise and use relationships between operations, including inverse operations (e.g. cancellation to simplify calculations and expressions; use conventional notation for priority of operations, including brackets, powers, roots and reciprocals) |
For teachers
This GCSE Maths lesson teaches inverse operations. By the end, students should be able to reverse a multi-step calculation by applying the correct inverse operation to every step, in the reverse order, to find an unknown starting value. It works through two worked examples and the mistakes examiners report.