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Let A_n= ( 3 4 )- ( 3 4 )^2+ ( 3 4 )^3+ +(-1)^ n-1 ( 3 4 )^n and B_n=1-A_n . Find a least odd natural number n₀ , so that B_n>A_n, n n₀ .

Correct answer

7

Step-by-step solution

B_n=1-A_n>A_n A_n - 1 6 Obviously, it is true for all even values of n . But, for aligned n & =1, & 3 4 & 1 6 aligned which is true for n=7 . Obviously, n₀=7

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