Question 27

Find the value of *n* so that may be the geometric mean between *a* and *b*.

Answer

G. M. of *a* and *b* is .

By the given condition,

Squaring both sides, we obtain

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A wheel makes 360 revolutions in one minute. Through how many radians does it turn in one second?

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The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, then find the number of terms.

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Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.

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- Q:-
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- Q:-
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- Q:-
Evaluate

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- Q:-
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- Q:-
How many terms of G.P. 3, 3

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Let S be the sum, P the product and R the sum of reciprocals of

*n*terms in a G.P. Prove that P^{2}R^{n}= S^{n}

- NCERT Chapter