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If cos(alpha-beta)+cos(beta-gamma)+cos(g...

If `cos(alpha-beta)+cos(beta-gamma)+cos(gamma-alpha)=-3/2` , prove that `cosalpha+cosbeta+cosgamma=sinalpha+sinbeta+singamma=0`

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To prove that \( \cos \alpha + \cos \beta + \cos \gamma = 0 \) and \( \sin \alpha + \sin \beta + \sin \gamma = 0 \) given that \( \cos(\alpha - \beta) + \cos(\beta - \gamma) + \cos(\gamma - \alpha) = -\frac{3}{2} \), we can follow these steps: ### Step 1: Rewrite the cosine differences Using the cosine difference identity, we can express each term in the equation: \[ \cos(\alpha - \beta) = \cos \alpha \cos \beta + \sin \alpha \sin \beta \] \[ ...
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Knowledge Check

  • If cosalpha + cosbeta + cosgamma =0= sinalpha + sinbeta + singamma , then

    A
    `sin^(2)alpha + sin^(2)beta + sin^(2)gamma = 3/2`
    B
    `sin^(2)alpha+ sin^(2)beta+ sin^(2)gamma =3/4`
    C
    `cos^(2)alpha + cos^(2)beta + cos^(2)gamma =3/2`
    D
    `cos2alpha + cos2beta + cos2gamma =-1`
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