ECZ 2018 · GCE Paper 2 · Question 2 — Sequences and Series

Question from ECZ 2018 · GCE Paper 2 · Question 2

(a) Simplify 7st315u3v2 × 5u3v28s3t2.[2]

Verified working — step 1

Multiply the fractions and gather powers.

(b) In a geometric progression, the third term is 29 and the fourth term is 227. Find

(b(i)) the first term and the common ratio,[3]

Verified working — step 1

Let the first term be a and the common ratio r.

(b(ii)) the sum of the first 5 terms of the geometric progression,[2]

Verified working — step 1

Since r < 1, Sn = a1 - rn1 - r.

(b(iii)) the sum to infinity.[2]

Verified working — step 1

Since |r| < 1, the sum to infinity is a1 - r.

The full step-by-step working and final answer are included with Premium — checked against ECZ marking standards.

Original examination question © Examinations Council of Zambia. Worked solution and commentary © G12 Titan — not to be reproduced without permission.

Have a different question?

Search it — if it is from a past paper or a school mock, chances are we have it worked out, or one that uses the same method.

Search any past-paper question

More Sequences and Series questions from past papers