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प्रश्न
The first term of a G.P. is –3 and the square of the second term is equal to its 4th term. Find its 7th term.
उत्तर
For a G.P.
First term, a = –3
It is given that,
(2nd term)2 = 4th term
`=>` (ar)2 = ar3
`=>` a2r2 = ar3
`=>` a = r
`=>` r = –3
Now, 7th term = ar6
= –3 × (–3)6
= –3 × 729
= –2187
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