Mathematics A-Level
proof of geometric sum
What proof of geometric sum means in Mathematics A-Level, as defined for WJEC.
Definition of proof of geometric sum
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Reference: WJEC
Writing S_n and r S_n, then subtracting the second equation from the first so all intermediate terms cancel, leaving (1 − r)S_n = a(1 − rⁿ).
Topics that use proof of geometric sum
- 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 proof of geometric sum in the exam
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