Home
Class 12
MATHS
If A+B+C=pi and cosA+cosB+cosC=0=sinA+si...

If A+B+C=`pi` and `cosA+cosB+cosC=0=sinA+sinB+sinC` then `cos3A+cos3B+cos3C=`

A

3

B

-3

C

0

D

1

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • DEMOIVRE'S THEOREM

    AAKASH SERIES|Exercise PRACTICE EXERCISE|64 Videos

  • DEMOIVRE'S THEOREM

    AAKASH SERIES|Exercise EXERCISE -I|10 Videos

  • DEFINITE INTEGRALS

    AAKASH SERIES|Exercise Exercise (Level-2)|38 Videos

  • DIFFERENTIAL EQUATIONS

    AAKASH SERIES|Exercise Practice Exercise|62 Videos

Similar Questions

Explore conceptually related problems

If A+B+C= pi and cos A+cos B+cos C=0=sin A+sin B+sin C , then sin 3A+sin 3B+sin 3C =

If cos A+ cos B + cos C =0 then cos 3A+ cos 3B + cos 3X

Assertion (A): If A, B, C are the angles of a triangle such that cos A + cos B + Cos C = 0 = sin A + sin B + sin C then cos 3A + cos 3B + cos 3C = -3 Reason (R) : If cos alpha + cos beta + cos gamma = 0 = sin alpha + sin beta + singamma then cos 3 alpha + cos 3 beta + cos 3 gamma = 3 cos (gamma+alpha+beta)

If cosA+cosB+cosC=0=sinA+sinB+sinC then cos^(2)((A-B)/2)=

If A+B+C=270^(@) then cos 2A+cos2B=cos2C+4sinA sinB sinC=

If A+B+C=pi and cos A = cos B cos C " then " cot B cot C =

If A+B+C=180^(@) then cos A+cos B-cosC=

AAKASH SERIES-DEMOIVRE'S THEOREM-EXERCISE -II
  1. If cosalpha+cosbeta+cosgamma=0=sinalpha+sinbeta+singamma then x^(sin(2...

    Text Solution

    |

  2. If cosalpha+coabeta+cosgamma=0=sinalpha+sinbeta+singamma then cos(alph...

    Text Solution

    |

  3. If A+B+C=pi and cosA+cosB+cosC=0=sinA+sinB+sinC then cos3A+cos3B+cos3C...

    Text Solution

    |

  4. If x^6+1=0, then x =

    Text Solution

    |

  5. find the roots x^(11)-x^7+x^4-1=0

    Text Solution

    |

  6. The number of common roots of 15th and of 25th roots of unity are

    Text Solution

    |

  7. The common roots of the equation x^(12)-1=0,x^4+x^2+1=0 are

    Text Solution

    |

  8. The product of all nth roots of unity (n gt 1) is

    Text Solution

    |

  9. The product of the distinct (2n)^(th) roots 1+isqrt3 is

    Text Solution

    |

  10. If alpha is a non real root of x^6=1 then (alpha^5+alpha^3+alpha+1)/(a...

    Text Solution

    |

  11. If 1,alpha1,alpha2,…..alpha(n-1) are the n^(th) roots of unity then (1...

    Text Solution

    |

  12. If 1,alpha1,alpha2,…..alpha(n-1) are the n^(th) roots of unity and n i...

    Text Solution

    |

  13. If alpha is an n^(th) root of unity then prove that 1+2alpha+3alpha^2+...

    Text Solution

    |

  14. Statement-I : ((costheta+isintheta)^5(cos3theta-isin3theta)^6)/((co...

    Text Solution

    |

  15. Statement-I : If xn=cos(pi//2^n)+isin (pi//2^n) then x1.x2.x3…..=-...

    Text Solution

    |

  16. Statement-I : If e^(itheta)=costheta+isintheta then for the DeltaABCe^...

    Text Solution

    |

  17. The ascending order of the values of z1=(1+i)^4,z2=(sqrt3+i)^(12),...

    Text Solution

    |

  18. The descending order of the values of z1=((sqrt3)/(2)i+1/2)^6,z2=(...

    Text Solution

    |

  19. If cosalpha+cosbeta+cosgamma=0=sinalpha+sinbeta+singamma, then match t...

    Text Solution

    |

  20. Match the following. {:("I) "(i)^i=,"a) "ipi//2),("II) "logei=,"b)...

    Text Solution

    |