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प्रश्न
If the 4th, 10th and 16th terms of a G.P. are x, y and z, respectively. Prove that x, y, z are in G.P.
उत्तर
Let the first term of the geometric progression = a,
Common ratio = r
∴ a4 = ar3 = x ....(1)
a10 = ar9 = y ....(2)
a16 = ar15 = z ....(3)
Dividing (2) by (1), we obtain
Dividing (3) by (2), we obtain
∴
Thus, x, y, z are in G.P.
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