Geometric sequences and seriesEdexcel International A Level Maths: Mind map

Exam questions on Geometric sequences and series

1. A geometric series has first term $6$ and common ratio $\frac12$.
   Find the exact sum of the first $8$ terms.2 marks
2. A geometric series has first term $5$ and common ratio $1.2$. Its $n$th term is $u_n$.
   Find the sum of the first $15$ terms, giving your answer to 3 significant figures.2 marks
3. A geometric series with positive common ratio has second term $24$ and fourth term $6$. The sum of the first $n$ terms is $S_n$.
   Find the first term and the common ratio.3 marks