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If `cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0` and `alpha+beta+gamma=0`, then `cos3alpha+8cos3beta+27sin3gamma=`

A

0

B

3

C

8

D

`-18`

Text Solution

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The correct Answer is:
a
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OBJECTIVE RD SHARMA-COMPLEX NUMBERS -Chapter Test
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  3. If cosalpha+2cosbeta+3cosgamma=sinalpha+2sinbeta+3singamma=0 and alpha...

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  6. If 2z1-3z2 + z3=0, then z1, z2 and z3 are represented by

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  7. Re((z+4)/(2z-1)) = 1/2, then z is represented by a point lying on

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  8. The vertices of a square are z1,z2,z3 and z4 taken in the anticlockwis...

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  9. Let lambda in R . If the origin and the non-real roots of 2z^2+2z+lam...

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  10. if the complex no z1 , z2 and z3 represents the vertices of an equ...

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  11. If P,P^(') represent the complex number z(1) and its additive inverse ...

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  12. Let A(z(1)),B(z(2)),C(z(3)) be the vertices of an equilateral triangle...

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  13. The area of the triangle (in square units) whose vertices are i, omega...

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  14. The complex number z satisfying |z+1|=|z-1| and arg (z-1)/(z+1)=pi/4, ...

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  15. If A,B,C are three points in the Argand plane representing the complex...

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  16. If z(bar(z+alpha))+barz(z+alpha)=0, where alpha is a complex constant,...

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  19. If z be a complex number, then |z-3-4i|^(2)+|z+4+2i|^(2)=k represent...

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