The 4th term of a G.P. is square of its second term, and the first term is –3. Determine its 7th term.

Asked by Abhisek | 1 year ago |  84

##### Solution :-

Let’s consider a to be the first term and r to be the common ratio of the G.P.

Given, a = –3

And we know that,

an = arn–1

So, a= ar3 = (–3) r3

a2 = a r1 = (–3) r

Then from the question, we have

(–3) r3 = [(–3) r]2

⇒ –3r3 = 9 r2

⇒ r = –3

a7 = a r 7–1 = a r6 = (–3) (–3)6 = – (3)7 = –2187

Therefore, the seventh term of the G.P. is –2187.

Answered by Pragya Singh | 1 year ago

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