Question:

If sumᵣ=0ⁿ(r+2)/(r+1)ⁿCᵣ=(2ⁿ-1)/(6), then n=

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Try small integer values of n in summation questions.

Updated On: Mar 19, 2026

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The Correct Option is B

Solution and Explanation

Using binomial identities and comparing values gives: n=4

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