Insert 6 geometric means between 27 and \( \dfrac{1}{81}\).

Asked by Aaryan | 1 year ago |  52

1 Answer

Solution :-

Let the six terms be a1, a2, a3, a4, a5, a6.

A = 27, B = \( \dfrac{1}{81}\)

Now, these 6 terms are between A and B.

So the GP is: A, a1, a2, a3, a4, a5, a6, B.

So we now have 8 terms in GP with the first term being 27 and eighth being \( \dfrac{1}{81}\).

We know that, Tn = arn–1

Here, Tn = \( \dfrac{1}{81}\), a = 27 and

\( \dfrac{1}{81}\)= 27r8-1

\(\dfrac{ 1}{(81×27)}\) = r7

r = \( \dfrac{1}{3}\)

a1 = Ar = 9

a2 = Ar2 = 3

a3 = Ar3 = 1

a4 = Ar4 = \( \dfrac{1}{3}\)

a5 = Ar5 = \( \dfrac{1}{9}\)

a6 = Ar6 = \( \dfrac{1}{27}\)

The six GM between 27 and \( \dfrac{1}{81}\) are 9, 3, 1, \( \dfrac{1}{3}\),\( \dfrac{1}{9}\)\( \dfrac{1}{27}\)

Answered by Aaryan | 1 year ago

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