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MathsMediumNumerical2020 · 07 Jan Shift 1

Q71.If the sum of the coefficients of all even powers of x in the product (1 + x + x2 + … + x2n)(1 −x + x2 −x3 + … + x2n) is 61, then n is equal to

What This Question Tests

This question tests the property of finding the sum of coefficients of even powers of x in a polynomial product. It requires evaluating the polynomial at x=1 and x=-1 and using the derived formula.

Concepts Tested

Binomial ExpansionSum of CoefficientsProperties of Polynomials

Formulas Used

Sum of coefficients of even powers = (P(1) + P(-1))/2

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