The th term of a sequence is given by for

MATHEMATICS · Subjective · A Level · Mathematics · Sequences and series · Sequences and series

Problem

The

n

th term of a sequence is given by

a_n = 5\, 2^{\,n-1}

for

n \ge 1

. Prove that the sequence

\{a_n\}

is a geometric progression and find its common ratio.