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# Finite geometric series in sigma notation

## Problem

The series 4, plus, 6, plus, 9 can be written using sigma notation (also called summation notation):
sum, start subscript, k, equals, 0, end subscript, start superscript, m, end superscript, a, start subscript, k, end subscript
Find m.
m, equals
Write an expression for a, start subscript, k, end subscript in terms of k.
a, start subscript, k, end subscript, equals
Stuck?
Stuck?