Back to the 2022 paper

Module 2: Mathematical Induction & Counting Techniques.

20227m

Use mathematical induction to prove this formula for the sum of a finite number of terms of a geometric progression with initial term aa and common ratio rr:
j=0narj=a+ar+ar2++arn=arn+1ar1\sum_{j=0}^{n} ar^j = a + ar + ar^2 + \dots + ar^n = \frac{ar^{n+1} - a}{r-1}
when $r
e 1where where n$ is a non-negative integer.

Similar questions