Home
Class 11
MATHS
If cos^2x+cos^2 2x+cos^2 3x=1 then (a) x...

If `cos^2x+cos^2 2x+cos^2 3x=1` then (a) `x=(2n+1)pi/4,\ n in I` (b) `x=(2n+1)pi/2,\ n in I` (c) `x=npi+-\ pi/6,\ n in I` (d) none of these

Promotional Banner

Topper's Solved these Questions

  • TRIGNOMETRIC RATIOS AND IDENTITIES

    ALLEN|Exercise All Questions|1 Videos

  • TRIGONOMETRIC RATIOS AND IDENTITIES

    ALLEN|Exercise All Questions|136 Videos

Similar Questions

Explore conceptually related problems

The general solution of cos x cos6x=-1 is x=(2n+1)pi,n in Zx=2n pi,quad n in Zx=n pi,n in Z(d) none of these

If cos2x-3cosx+1=(cos e c\ x)/(cotx-cot2x),\ then which of the following is true ? x=(2n+1)\ pi/2,\ n\ in I (b) x=2npi,\ n in I x=2npi+-cos^(-1)(2/5),\ n in I (d) no real x

The function (sin(x+a))/(sin(x+b)) has no maxima or minima if (a) b-a=n pi,n in I(b)b-a=(2n+1)pi,n in I(c)b-a=2n pi,n in I(d) none of these

The general solution of the equation 2^(cos2x)=1=3.2^(-sin^2x) is (A) n pi,n epsilon i (B) (n+1/2) pi, n epsilon I (C) (n- 1/2) pi, n epsilon I (D) none of these

If 4cos^(2)theta+sqrt(3)=2(sqrt(3)+1)cos theta, then theta is 2n pi+-(pi)/(3),n in I(b)2n pi+-(pi)/(4),n in I2n pi+-(pi)/(6),n in I(d) none of these

The straight line x cos theta+y sin theta=2 will touch the circle x^(2)+y^(2)-2x=0 if theta=n pi,n in IQ(b)A=(2n+1)pi,n in Itheta=2n pi,n in I(d) none of these

If sinx+cosy=1 and cos2x-cos2y=1 then the values of x and y are (A) x=npi+(-1)^n pi/3, n in I, y=mpi+-pi/6, m in I (B) x=npi+(-1)^n pi/6, n in I, y=mpi+-pi/3, m in I (C) x=npi+(-1)^n pi/4, n in I, y=mpi+-pi/4, m in I (D) none of these

If cos ecx=1+cot x then x=2n pi,2n pi+(pi)/(2)

Which of the following is not the general solution of 2^(cos2x)+1=3. 2^-sin^(2x)? (a)npi,n in Z (b) (n+1/2)pi,n in Z (n-1/2)pi,n in Z (d) none of these

General solution for |sin x|=cos x is 2n pi+(pi)/(4),n in I(b)2n pi+-(pi)/(4),n in1n pi+(pi)/(4),n in1(d) none of these

ALLEN-TRIGONOMETRIC EQUATION-All Questions
  1. General solution for |sinx|=cosx is (a) 2npi+pi/4,\ n in I (b) 2npi+-...

    Text Solution

    |

  2. The most general value for which tantheta=-1costheta=1/(sqrt(2))i s(n ...

    Text Solution

    |

  3. If cos^2x+cos^2 2x+cos^2 3x=1 then (a) x=(2n+1)pi/4,\ n in I (b) x=(2...

    Text Solution

    |

  4. If 4\ cos^2theta+sqrt(3)=2(sqrt(3)+1)costheta, then theta is (a) 2npi+...

    Text Solution

    |

  5. Set of values of 'alpha' in [0,\ 2pi] for which m=(log)(("x"+1/"x"))(2...

    Text Solution

    |

  6. (a+2)sinalpha+(2a-1)cosalpha=(2a+1)iftanalpha"i s" 3/4 (b) 4/3 (c) ...

    Text Solution

    |

  7. The number of solution(s) of the equation cos2theta=(sqrt(2)+1)(cos...

    Text Solution

    |

  8. The value(s) of theta , which satisfy 3-2\ costheta-4sintheta-cos2thet...

    Text Solution

    |

  9. Given that A ,\ B are positive acute angles and sqrt(3)\ sin2A=sin2B...

    Text Solution

    |

  10. The value(s) of theta, which satisfy the equation : 2cos^3 3thetath...

    Text Solution

    |

  11. The solution(s) of the equation sin7x+cos2x=-2 is/are x=(2kpi)/7+(3...

    Text Solution

    |

  12. n|sinx|= m |cos| in [0, 2pi] where n > m and are positive integers

    Text Solution

    |

  13. 2^1|cosx|+|cosx|^(2 dotx)=4\ \ in\ (-pi,pi)

    Text Solution

    |

  14. Statement - I : For any real value of theta!=(2n+1)pior\ (2n++1)pi/...

    Text Solution

    |

  15. Statement - I : The equation sqrt(3)cosx-sinx=2 has exactly one ...

    Text Solution

    |

  16. Statement - I : General solution of (tan4x-tan2x)/(1+tan4xtan2x)=1\...

    Text Solution

    |

  17. Statement - I :The equation sin(cos x) has no real solution. Becaus...

    Text Solution

    |

  18. If sinA=s in Ba n dcosA=cosB , then find the value of A in terms of Bd...

    Text Solution

    |

  19. Solve the equation: 1 + 2 cosecx = -(sec^2 (x/2))/2

    Text Solution

    |

  20. Solve: sin3alpha=4sinalphasin(x+alpha)sin(x-alpha),w h e r ealpha!=npi...

    Text Solution

    |