Mathematics A-Level
sum of geometric series
What sum of geometric series means in Mathematics A-Level, as defined for WJEC.
Definition of sum of geometric series
Check what you remember
Read the wording for your board, then hide it and explain sum of geometric series in your own words. Rough notes are fine. This is a self-check, with no mark or grade.
Reference: WJEC
The sum of the first n terms of a finite geometric series, S_n = a(1 − rⁿ) / (1 − r) for r ≠ 1.
Topics that use sum of geometric series
- Sequences and Series (A2 Unit 3: Pure Mathematics B) (WJEC A-Level)
Related terms
- Arithmetic sequence
- binomial approximation
- common difference
- compound growth and depreciation
- Convergent geometric series
- Geometric sequence
- infinite binomial series
- linearity of summation
Using sum of geometric series in the exam
Check the command word and mark scheme for your exact question. After comparing your explanation with the reference, use the term in an answer on the linked topic. This practice does not predict an exam mark.
Practise Mathematics questions
Create a free account to answer exam-style questions on this topic and get feedback on your answers.
Start free
All Mathematics A-Level termsA week of Premium from your first lesson · Then the free plan continues · No card, no charge