A-Level Maths - Core/Pure 1
Geometric Series - Proof of the Sum of the first n terms : ExamSolutions
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Formulae for geometric series and converging geometric series
A geometric series sum_(k)a_k is a series for which the ratio of each two consecutive terms a_(k+1)/a_k is a constant function of the summation index k. The more general case of the ratio a rational function of the summation index k produces a series called a hypergeometric series. For the simplest case of the ratio a_(k+1)/a_k=r equal to a constant r, the terms a_k are of the form a_k=a_0r^k. Letting a_0=1, the geometric sequence {a_k}_(k=0)^n with constant |r|<1 is given by ...
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