Question

Determine the 15th term of the sequence1,-2,4​

Answer 1

Answer:

16384

Step-by-step explanation:

The sequence is 1, -2, 4, ...........

This is a geometric sequence with first term 1 and common ratio - 2.

Hence, the 15th term of the sequence is = $1 \times (- 2)^{(15 - 1)} = (- 2)^{14} = 16384$ (Answer)

The nth term of an G.P. with first term a and common ratio r is given by $a\times r^{(n - 1)}$