Question

The first term of a G.P. is –3 and the square of the second term is equal to its 4^th term. Find its 7^th term.

Answer 1

For a G.P.

First term, a = –3

It is given that,

(2^nd term)² = 4^th term

`=>` (ar)² = ar³

`=>` a²r² = ar³

`=>` a = r

`=>` r = –3

Now, 7^th term = ar⁶

= –3 × (–3)⁶

= –3 × 729

= –2187