Substituting into and transposing formulas to find an unknown value

What this note covers

1. What a formula is doing, and what the exam expects you to do with it
2. Substitution done carefully: units, brackets and one line at a time
3. Show that questions: what full working actually means
4. Transposition: the mechanics of changing the subject
5. Transpose first or substitute first? Choosing the efficient route
6. Formulas you will actually meet, and how to read an unfamiliar one
7. A full worked question in exam shape
8. How formula questions are marked, and what a top-band script shows

8 sections · 12 key terms & formulas · 6 common mistakes