Q5 — Geometric sequence: nth term and missing term (4 marks)

Question (4 marks):

A geometric sequence has first term $3$ and common ratio $4$.

(a) Write down the first four terms. (1)

(b) Find a formula for the $n$th term. (1)

(c) The $k$th term equals $3072$. Find the value of $k$. (2)

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