Find the 20th and nthterms of the G.P. 5/2, 5/4, 5/8, ………

Asked by Abhisek | 1 year ago |  79

1 Answer

Solution :-

Given G.P. is \( \dfrac{5}{2}\), \( \dfrac{5}{4}\), \( \dfrac{5}{8}\), ………

Here, a = First term = \( \dfrac{1}{2} \)

r = Common ratio = (5/4)/(5/2) = \( \dfrac{1}{2} \)

Thus, the 20th term and nth term

\( a_{20}=ar^{20-1} =\dfrac{5}{2}(\dfrac{1}{2})^{19} \)

\( \dfrac{5}{(2)^{20}}\)

\( a_n=ar^{n-1} =\dfrac{5}{2}(\dfrac{1}{2})^{n-1} \)

\( \dfrac{5}{(2)^n}\)

Answered by Pragya Singh | 1 year ago

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