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If alpha=cos((8pi)/11+isin((8pi)/11 then...

If `alpha=cos((8pi)/11+isin((8pi)/11` then `Re(alpha+alpha^2+alpha^3+alpha^4+alpha^5)` is

A

(1/2)

B

(-1/2)

C

0

D

none of these

Text Solution

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The correct Answer is:
B
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PATHFINDER-COMPLEX NUMBER-QUESTION BANK
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  2. If a=cosalpha+isinalpha , b=cosbeta+isinbeta , c=cosgamma+isingamma an...

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  3. If alpha=cos((8pi)/11+isin((8pi)/11 then Re(alpha+alpha^2+alpha^3+alph...

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  4. If z be any complex number such that abs(3z-2)+abs(3z+2)=4 then locus ...

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  5. x^(3m)+x^(3n-1)+x^(3r-2) where m,n,r in N is divisible by

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  6. A fourth root of -1 is

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  7. If z1=a+ib and z2=c+id are complex numbers such that abs(z1)=abs(z2)=1...

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  8. Let z1 and z2 be complex numbers such that z1 nez2 and absz1=absz2 if ...

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  9. If (x+2)^3-27=0 then a value of x is

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  10. If absomega=1 then the set of points z=omega+1/omega is contained in o...

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  11. If z1 lies on absz=1 and z2 lies on absz=2 then

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  12. IfA(z1),B(z2),C(z3) and D(z4) be the vertices of the square ABCD then

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  13. If z1 and z2 are non zero complex numbers such that abs(z1-z2)=absz1+a...

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  14. The reflection of the complex number (2-i)/(3+i) where (i=sqrt(-1)in t...

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  15. If alpha is a complex constant such that alphaz^2+z+baralpha=0 has are...

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  16. Let A,B,C b ethree sets of complex numbers as defined A={z:Im zge 1} ...

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  17. Let A,B,C b ethree sets of complex numbers as defined A={z:Im zge 1} ...

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  18. Let alpha+ibeta be a complex number and let x+iy=e^(alpha+ibeta) where...

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  19. Let alpha+ibeta be a complex number and let x+iy=e^(alpha+ibeta) where...

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  20. If alpha is non real fourth root of unity , then value of,alpha^(4n-1)...

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