QOD-31/05/13

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P_n=(1+x)(1-x²)(1+x³)....(1-x⁴ⁿ)[(1+x)(1-x²)(1+x³)....(1-x²ⁿ)]²

Find lim(xâ†’-1)P_n

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4 Answers

283

Sahil Jain ·2014-06-14 04:17:10

dividing the numerator and denominator by (1-x)⁴ⁿ
writing like this
(1-x)(1-x)............(1-x)4n time for numerator
so it wil become 1.2.3.4......4n
for denomintor
(1-x)(1-x)....(1-x) 2n times
so it will be 1.2.3.4.5.6....2n)²
4nfacotrial / (2nfactorial)²
so ans is ⁴ⁿC_2n

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11

Debargha Paul ·2013-05-31 00:56:07

1???

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1357

Manish Shankar ·2013-06-08 07:00:42

Try this

answer is ⁴ⁿC_2n

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1357

Manish Shankar ·2014-06-09 23:24:47

???

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