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MathsHardMCQ2023 · 24 Jan Shift 2

Q65.If (30C1)2 + 2(30C2)2 + 3(30C3)2. . . . . . . . . . 30(30C30)2 = (30!)2α60! , then (1) 30 (2) 60 (3) 15 (4) 10

What This Question Tests

This question tests advanced summation identities involving squares of binomial coefficients, requiring a non-trivial manipulation to arrive at the solution.

Concepts Tested

Binomial coefficientsSummation properties of binomial coefficients

Formulas Used

k * (nCk)² = n * (n-1)Ck-1 * nCk

Σ (nCk)² = 2nCn

(nCk) = n! / (k! * (n-k)!)

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