Home
Class 12
MATHS
If alpha in [-2pi, 2pi] and cos.(alpha)/...

If `alpha in [-2pi, 2pi]` and `cos.(alpha)/(2)+sin.(alpha)/(2)=sqrt(2)(cos 36^(@)-sin18^(@))`, then a value of `alpha`

A

`(7pi)/(6)`

B

`(pi)/(6) `

C

`-(5pi)/(6)`

D

`-(pi)/(6)`

Text Solution

Verified by Experts

The correct Answer is:
A, D
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC EQUATIONS AND INEQUATIONS

    ARIHANT MATHS|Exercise Exercise (Passage Based Questions)|13 Videos

  • TRIGONOMETRIC EQUATIONS AND INEQUATIONS

    ARIHANT MATHS|Exercise Exercise (Single Integer Answer Type Questions)|12 Videos

  • TRIGONOMETRIC EQUATIONS AND INEQUATIONS

    ARIHANT MATHS|Exercise Exercise (Single Option Correct Type Questions)|60 Videos

  • THREE DIMENSIONAL COORDINATE SYSTEM

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|44 Videos

  • TRIGONOMETRIC FUNCTIONS AND IDENTITIES

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|19 Videos

Similar Questions

Explore conceptually related problems

cos((alpha)/(2))+sin((alpha)/(2))=sqrt(2)(cos36^(@)-sin18^(@))

sin alpha-sin2 alpha+sin3 alpha=4cos(3 alpha)/(2)cos alpha sin(alpha)/(2)

If (pi)/(2)ltalphalt(2pi)/(3)andl=int_(0)^(sin2alpha)(dx)/(sqrt(4cos^(2)alpha-x^(2))) , then the value of (l+alpha)/(pi) must be__________.

If sin alpha = -3/5 , pi lt alpha lt 3pi/2 then cos alpha/2 = 1/sqrt10

(sqrt2 - sin alpha - cos alpha )/( sin alpha - cos alpha)=

If sin alpha = (-3)/(5), where pi lt alpha lt (3pi)/(2), then cos ((alpha)/(2))=

If A=[cos alpha+sin alpha sqrt(2)sin alpha-sqrt(2)sin alpha cos alpha-sin alpha], prove that =[cos n alpha+sin n alpha sqrt(2)sin n alpha-sqrt(2)sin n alpha cos n alpha-sin n alpha] for all n in N.

If 0

If pi

ARIHANT MATHS-TRIGONOMETRIC EQUATIONS AND INEQUATIONS-Exercise (More Than One Correct Option Type Questions)
  1. The equation 2sin^3theta+(2lambda-3)sin^2theta-(3lambda+2)sintheta-2la...

    Text Solution

    |

  2. If x+y=2pi//3 and sin x//siny=2, then the

    Text Solution

    |

  3. If 0 le x le 2pi and |cos x | le sin x , the

    Text Solution

    |

  4. If x and y are positive acute angles such that (x+y) and (x-y) satisf...

    Text Solution

    |

  5. If x+y=(4pi)/(3) and sin x = 2 sin y , then

    Text Solution

    |

  6. The number of solutions of the equations y=1/3[sin theta+[sin theta +[...

    Text Solution

    |

  7. If [sin x]+[sqrt(2) cos x]=-3 , x in [0,2pi], (where ,[.] denotes th ...

    Text Solution

    |

  8. If alpha in [-2pi, 2pi] and cos.(alpha)/(2)+sin.(alpha)/(2)=sqrt(2)(co...

    Text Solution

    |

  9. The number of value of alpha in the interval [-pi,0] satisfying sin...

    Text Solution

    |

  10. Find the number of solution of theta in [0,2pi] satisfying the equatio...

    Text Solution

    |

  11. If alpha and beta are the solution of a cos theta + b sin theta = c...

    Text Solution

    |

  12. The solution of the equation sin 2x + sin 4x = 2 sin 3x is

    Text Solution

    |

  13. The general solution of 4sin^(4) x + cos^(4) x=1 is

    Text Solution

    |

  14. The value of x , 0 le x le (pi)/2 which satisfy the equation 81^( si...

    Text Solution

    |

  15. The value of x in (0,pi/2) satisfying (sqrt(3)-1)/(sinx)+(sqrt(3)+1)/(...

    Text Solution

    |

  16. The values of alpha for which the equation alpha^2/(1-tan^2x)=(sin^2...

    Text Solution

    |

  17. For which values of a does the equation 4sin(x+pi/3)cos(x-pi/6)=a^2+sq...

    Text Solution

    |

  18. Which of the following is/are correct .

    Text Solution

    |

  19. The value of theta , lying between theta =0 and theta=(pi)/(2) and ...

    Text Solution

    |

  20. If [x] dnote the greatest integer less than or equal to x then the equ...

    Text Solution

    |