Q6 of 176 Page 21

Mark the correct alternative in each of the following:

If S be the sum, P the product and R be the sum of the reciprocals of n terms of a GP, then is equal to


Let the GP is a , ar , ar2 , ar3 , .......... arⁿ⁻1.


S = Sum of n terms


= a + ar + ar2 + ar3 + .......+ arⁿ⁻1



and R = sum of reciprocal of n terms





P = product of n terms = a × ar × ar2 × ar3 × .....× arⁿ⁻1


=(a1⁺1⁺1⁺1⁺1⁺1⁺1⁺⁻⁻1)(r1⁺2⁺3⁺⁻⁻⁻⁻⁽ⁿ⁻1⁾〉



take square both sides,



⇒


⇒


⇒


Thus,


⇒

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