If `alpha` is an imaginary root of `z^n -1=0` then `1+alpha+alpha^2+………_+alpha^(n-1)=` (A) 1 (B) -1 (C) 0 (D) 2

If alpha is an n^(th) roots of unity, then 1+2alpha+3alpha^(2)+……..+nalpha^(n-1) equals

If alpha is an imaginary fifth root of unity, then log_(2)|1+alpha+alpha^(2)+alpha^(3)-1/alpha|=

If alpha is an imaginary roots of x^(5)-1=0, then the equation whose roots are alpha+alpha^(4) and alpha^(2)+alpha^(3) is

if alpha and beta are the roots of the equation x^(2)+x+1=0 then alpha^(28)+beta^(28)=(A)1(B)-1(C)0(D)2

Let (z-alpha)/(z+alpha) is purely imaginary and |z|=2, alpha in RR then alpha is equal to (A) 2 (B) 1 (C) sqrt2 (D) sqrt3

If 1,alpha_1, alpha_2, …alpha_(n-1) be nth roots of unity then (1+alpha_1)(1+alpha_2)……....(1+alpha_(n-1))= (A) 0 or 1 according as n is even or odd (B) 0 or 1 according as n is odd or even (C) n (D) -n

if alpha and beta are imaginary cube root of unity then prove (alpha)^(4)+(beta)^(4)+(alpha)^(-1)*(beta)^(-1)=0

If alpha and beta are the roots of the equation x^(2)-x+1=0, then alpha^(2009)+beta^(2009)=-1 (b) 1( c) 2(d)-2

If alpha is the nth root of unity,then 1+2 alpha+3 alpha^(2)+rarr n terms equal to a.(-n)/((1-alpha)^(2)) b.(-n)/(1-alpha^(2)) c.(-2n)/(1-alpha) d.(-2n)/((1-alpha)^(2))