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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 Terms Using the cosine of difference identity, we can rewrite the given expression: \[ \cos(\alpha - \beta) = \cos \alpha \cos \beta + \sin \alpha \sin \beta \] \[ ...
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If alpha,beta,gamma are the angles of a triangle and system of equations cos(alpha-beta)x+cos(beta-gamma)y+cos(gamma-alpha)z=0 cos(alpha+beta)x+cos(beta+gamma)y+cos(gamma+alpha)z=0 sin(alpha+beta)x+sin(beta+gamma)y+sin(gamma+alpha)z=0 has non-trivial solutions, then triangle is necessarily a. equilateral b. isosceles c. right angled "" d. acute angled

If 2(cos ( alpha-beta)+cos(beta-gamma)+cos(gamma-alpha)+3=0 , prove that (d alpha)/(sin ( beta+theta)sin(gamma+theta))+(d beta)/(sin(alpha+beta)sin(beta+theta))+(d gamma)/(sin(alpha+theta)sin(beta+theta))=0 , where, 'theta' is any real angle such that alpha+theta, beta+theta, gamma+theta are not the multiple of pi .

If cos(alpha+beta)*sin(gamma+delta)=cos(alpha-beta)*sin(gamma-delta), prove that cotalphacotbetacotgamma=cotdelta

If cosalpha+cosbeta+cosgamma=0 , then prove that cos3alpha+cos3beta+cos3gamma=12cosalphacosbetacosgamma

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

If cosalpha+cosbeta+cosgamma=0 a n d a l so sinalpha+sinbeta+singamma=0, then prove that cos2alpha+cos2beta+cos2gamma =sin2alpha+sin2beta+sin2gamma=0 sin3alpha+sin3beta+sin3gamma=3sin(alpha+beta+gamma) cos3alpha+cos3beta+cos3gamma=3cos(alpha+beta+gamma)

If alpha+beta+gamma=pi , prove that : cos^2 alpha + cos^2 beta + cos^2 gamma+2cosalpha cosbeta cosgamma=1 .

The expression cos^(2)(alpha + beta + gamma) + cos^(2)(beta + gamma) + cos^(2)alpha - 2cos alpha cos(beta + gamma)cos(alpha + beta + gamma) is (a) independent of alpha (b) independent of beta (c) dependent on gamma only (d) dependent on alpha, beta, gamma

If cos(alpha+beta)sin(gamma+delta)="cos"(alpha-beta)"sin"(gamma-delta) , prove that cotalphacotbetacotgamma=cotdelta

If alpha,beta,gamma, in (0,pi/2) , then prove that (s i(alpha+beta+gamma))/(sinalpha+sinbeta+singamma)<1

RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS OF COMPOUND ANGLES-All Questions
  1. It cos(alpha+beta)=4/5,sin(alpha-beta)=5/(13)a n dalpha,beta lie betwe...

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  2. If tanA-tanB=x a n dcotB-cotA=y , prove that cot(A-B)=1/x+1/y

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  3. If cos(alpha-beta)+cos(beta-gamma)+cos(gamma-alpha)=-3/2 , prove that...

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  4. If sinB=3sin(2A+B) ,prove :2tanA+tan(A+B)=0.

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  5. If 2tanbeta+cotbeta=tanalpha , prove that cotbeta=2tan(alpha-beta)dot

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  6. If the system of linear equations x=cy+bz, y=az+cx,z=bx+ay has a non t...

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  7. Prove that: tan3Atan2AtanA=t a n3A-tan2A-t a n A cot Acot2A-cot2Aco...

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  8. Prove that: sin^2(pi/8+A/2)-sin^2(pi/8-A/2)=1/sqrt(2)sinA

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  9. Prove that: sin^2A=cos^2(A-B)+cos^2B-2cos(A-B)cosAcosBdot

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  10. If 3t a n At a n B=1, prove that 2cos(A+B)=cos(A-B)dot

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  11. Prove that: tan75^0+cot75^0=4

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  12. If alphaa n dbeta are the solutions of acostheta+bsintheta=c , then ...

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  13. If alpha a n d beta are the solutions of the equation at a ntheta+bs e...

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  14. If (sin(x+y))/(sin(x-y))=(a+b)/(a-b) , show that (tanx)/(tany)=a/b .

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  15. If t a n(pi//4+theta)+t a n(pi//4-theta)=a , then t a n^2(pi//4+theta...

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  16. If t a n x+tan(x+pi/3)+tan(x+(2pi)/3)=3, then prove that (3tanx-t a n^...

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  17. If theta lies in the first quadrant and costheta=8/(17) , then prove t...

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  18. If tan(A-B)=1,sec(A+B)=2/(sqrt(3)) , then the smallest positive value ...

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  19. If t a nbeta=(nsinalphacosalpha)/(1-nsin^2alpha) , show that tan(alph...

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  20. If A+B=pi/4 , prove that: (1+t a n A)(1+t a n B)=2 (cotA-1)(cot...

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