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Prove that underset(r=0)overset(n)sum.^(...

Prove that `underset(r=0)overset(n)sum.^(n)C_(r)(-1)^(r)[i^(r)+i^(2r)+i^(3r)+i^(4r)]`
`=2^(n) + 2^(n+1)cos (npi//4)` , where `i = sqrt(-1)`

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CENGAGE PUBLICATION-BINOMIAL THEOREM-All Questions
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  2. Let a=(2^(1//401)-1) and for each ngeq2,l e tbn=^n C1+^n C2dota+^n C3...

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  3. Prove that underset(r=0)overset(n)sum.^(n)C(r)(-1)^(r)[i^(r)+i^(2r)+i^...

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  4. The coefficients of x^n in (1+x/(1!)+x^2/(2!)+……+x^n/(n!))^2 is

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  5. If the first and third term is 2 and 8 respectively. Find its secon...

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  6. Find the next two terms of the series 2,-6,18,-54,.....

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  11. sum(k=1)^ook(1-1/n)^(k-1) =?

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  16. The value of underset(r=0)overset(20)sum(-1)^(r )(.^(50)C(r))/(r+2) is...

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  18. If a, b, c are in GP and a, x, b,y, c ar in AP. then prove that, 1...

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  19. Statement 1: ""^m Cr+ ""^m C(r-1)(""^nC1)+ ""^mC(r-2)(""^n C2)+....+ "...

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