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If cosalpha+cosbeta+cosgamma=0=sinalpha+...

If `cosalpha+cosbeta+cosgamma=0=sinalpha+sinbeta+singamma`, then which of the following is/are true:- (a)`cos(alpha-beta)+cos(beta-gamma)+cos(gamma-delta)=-3/2` (b)`cos(alpha-beta)+cos(beta-gamma)+cos(gamma-delta)=-1/2` (c)`sumcos2alpha+2cos(alpha+beta)+2cos(beta+gamma)+2cos(gamma+alpha)=0` (d)`sumsin2alpha+2sin(alpha+beta)+2sin(beta+gamma)+2sin(gamma+alpha)=0`

A

A is true and B is false

B

A is false and B is true

C

both A and B are true

D

both A and B are false

Text Solution

Verified by Experts

The correct Answer is:
C
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