Home
Class 12
MATHS
If cos (81^(@) + theta) = sin(k/3 - the...

If ` cos (81^(@) + theta) = sin(k/3 - theta)` , then k is equal to

A

`9^(@) `

B

`30^(@)`

C

`27^(@)`

D

`45^(@)`

Text Solution

Verified by Experts

The correct Answer is:
C
We have, ` cos(81^(@) + theta)= sin(k/3 - theta)`
` Rightarrow 81^(@)+ theta + k/3 - theta = 90^(@) " " [ therefore cos prop = sin beta , "then" prop + beta = 90^(@)]`
` Rightarrow k/3 = 90^(@) -81^(@) Rightarrow k= 27^(@)`
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC FUNCTIONS

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise EXERCISE 1 Trigonomertric Ratio of Allied Angle|18 Videos

  • THREE DIMENSIONAL GEOMETRY

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise MHT CET Corner|3 Videos

  • TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES

    MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS|Exercise Exercise 2 (MISCELLANEOUS PROBLEMS)|20 Videos

Similar Questions

Explore conceptually related problems

If sin theta = sqrt3 cos theta, then theta is equal to

If sin^6 theta + cos^6 theta + k sin^2 2theta =1 , then k is equal to :

Maximum value of 8^(cos theta)16^(sin theta) is (8)^(k-1/3) ,then k is equal to

int(d theta)/(sin theta cos^(3)theta) is equal to

The value of 2 sin^2 theta + k cos^2 2 theta =1 , then k is equal to :

If 3sin theta-4cos theta=5 and 4sin theta+3cos theta=k, then k^(2) is equal to

If the expression (sin7 theta-sin3 theta)/(cos3 theta+cos7 theta)=tan k theta ,where k in N ,then k is equal to

If sin^(3) theta+sin theta cos theta+ cos^(3) theta=1 , then theta is equal to (n in Z)

MHTCET PREVIOUS YEAR PAPERS AND PRACTICE PAPERS-TRIGONOMETRIC FUNCTIONS -EXERCISE 2 (MISCELLANEOUS PROBLEMS)
  1. If DeltaABC right angle at B, BC = 5 cm and AC -AB =1 cm. then (1 ...

    Text Solution

    |

  2. If tan theta + cot theta =2, " then " tan^(2) theta + cot^(2) theta i...

    Text Solution

    |

  3. If cos (81^(@) + theta) = sin(k/3 - theta) , then k is equal to

    Text Solution

    |

  4. If sin theta = cos theta ,then the value of 2 tan^(2) theta + sin^(2)...

    Text Solution

    |

  5. If tan x = sin45^(@) cos 45^(@) + sin 30^(@) then x is equal to

    Text Solution

    |

  6. sin^(6) theta + cos^(6) theta is equal to

    Text Solution

    |

  7. cos^(2)5^(@) +cos^(2)10^(@) + cos^(2) 15^(@) +…..+cos^(2) 85^(@) + cos...

    Text Solution

    |

  8. (sin(90^(@) -theta)sin theta)/(tan theta) + sin^(2) theta is equal to

    Text Solution

    |

  9. If tantheta=(20)/(21) , show that (1-sintheta+costheta)/(1+sintheta...

    Text Solution

    |

  10. For 0 le theta le pi/2 the maximum value of sin theta + cos theta i...

    Text Solution

    |

  11. (cos 70^(@))/(sin 20^(@)) + (cos 59^(@))/(sin 31^(@) ) - 8 sin^(2) 30^...

    Text Solution

    |

  12. If sin theta = 1/2 and theta is acute then (3 cos theta -4 cos^(3) ...

    Text Solution

    |

  13. If 3 sin theta + 4 cos theta =5 , then value of sin theta is

    Text Solution

    |

  14. If theta "is theta " and (cos^(2)theta)/(cot^(2) theta -cos^(2) theta)...

    Text Solution

    |

  15. The value of (1+cos (pi/6))(1+cos(pi/3))(1+cos ((2pi)/3))(1+cos((7pi...

    Text Solution

    |

  16. If cos 20^(@) - sin 20^(@) =p " then " cos 40^(@) is equal to

    Text Solution

    |

  17. If Sn=cos^ntheta+sin^n tehta then find teh value of 3S4-2S6

    Text Solution

    |

  18. If cos x + cos^(2) x =1 then the value of sin^(12) x + 3 sin^(10)...

    Text Solution

    |

  19. If x sin^3theta+ycos^3theta=sinthetacostheta and xsintheta=ycostheta ...

    Text Solution

    |

  20. If theta in the first quadrant and 5 tan theta =4 " then " ( 5 sin ...

    Text Solution

    |