Question 17

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.

Answer

Let *a* be the first term and *r* be the common ratio of the G.P.

According to the given condition,

*a*_{4} = *a* *r*^{3} = *x* … (1)

*a*_{10} = *a* *r*^{9} = *y* … (2)

*a*_{16} = *a r*^{15} = *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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Pranshu krishan
2017-10-02 19:09:43

Thanks easy to learn!!!!!

sarthak tripathi
2017-08-13 19:46:05

nice solution ticki

bandhana
2017-02-24 17:07:23

Thanks , really its very helpful for me

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