Home
Class 12
MATHS
Let alpha, beta be such that pi lt alph...

Let `alpha, beta ` be such that `pi lt alpha lt beta lt 3pi,` if `sin alpha + sin beta =- (21)/(65) and cos alpha + cos beta =(27)/(65), ` then the value of `cos ""(alpha - beta)/(2)` is-

A

`-(3)/(sqrt130)`

B

`-(6)/(65)`

C

`(6)/(65)`

D

`(3)/(sqrt130)`

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 7|90 Videos

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 8|90 Videos

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 3|90 Videos

  • MCQ ZONE 3

    CHHAYA PUBLICATION|Exercise Question Paper 8|30 Videos

  • Measures of Central Tendency

    CHHAYA PUBLICATION|Exercise Exercise 2 C Very short answer type question|18 Videos

Similar Questions

Explore conceptually related problems

Let alpha,beta be such that pi lt alpha-beta lt3 pi . If sin alpha+ sin beta=(-21)/65 and cos alpha+ cos beta=(-27)/65 , then the value of cos((alpha-beta)/2) is

In sin alpha+ sin beta=(1)/(2) and cos alpha+ cos beta =(5)/(4) , find the value of tan alpha+tan beta .

If sin alpha + sin beta = p "and" cos alpha + cos beta = q "then the value of " "tan" (alpha-beta)/2 will be-

If cos alpha + cos beta =cos ""(3pi)/(7)and sin alpha + sin beta = sin ""(3pi)/(7), then the value of cos ^(2)""(alpha-beta)/(2) is-

If sin alpha = sin beta and cos alpha = cos beta then-

IF cos (alpha +beta )=(5)/(13) and cos (alpha - beta )=(4)/(5), then find the value of tan 2 beta .

sin alpha + sin beta = a "and" cos alpha + cos beta = b cos (alpha + beta) =

sin alpha + sin beta = a "and" cos alpha + cos beta = b sin (alpha + beta) =

If 0 lt alpha lt (pi)/(2) and sin alpha + cos alpha = sqrt2, then the value of cos 3 alpha is-

If sin 2 alpha + sin 2 beta = 3 "and" cos 2 alpha + cos 2 beta = 4,"then"- tan2 (alpha + beta)=

CHHAYA PUBLICATION-MCQ's-QUESTION PAPER 5
  1. The numbers tan (-(11pi)/(6)), tan((21pi)/(4))and cot ((283pi)/(6)) a...

    Text Solution

    |

  2. If cos A""1/7 and cos B= 13/14, where A and B both are acute angles, ...

    Text Solution

    |

  3. Let alpha, beta be such that pi lt alpha lt beta lt 3pi, if sin alpha...

    Text Solution

    |

  4. If 12 cot ^(2) theta -31 cosec theta + 32=0, then the value of sin the...

    Text Solution

    |

  5. If theta and phi are positive acute angles satisfying sin theta =1/2 a...

    Text Solution

    |

  6. The maximum value of (4 sin ^(2)x + 3 cos ^(2) x) is-

    Text Solution

    |

  7. If alpha, beta , gamma are angles of a triangle then the value of (sin...

    Text Solution

    |

  8. Let n be a natural number such that n gt 4 and U(n) =sin ^(n) x+ cos ^...

    Text Solution

    |

  9. If x=sin ^(2) theta + cosec ^(2) theta, then which one of the followin...

    Text Solution

    |

  10. The value of sin 47^(@) -sin 25^(@)+sin 61^(@)-sin 11^(@) is-

    Text Solution

    |

  11. If 0 lt theta lt pi/2 and sin 2 theta = cos 3 theta, then the value ...

    Text Solution

    |

  12. If in a DeltaABC, the altituds drawn from the vertices A,B, C on oppos...

    Text Solution

    |

  13. If cos A =3/4 then, the value of sin ""A/2sin ""(5A)/(2) is-

    Text Solution

    |

  14. If tan ""(alpha pi)/(4) =cot ""(beta pi)/(4), then which one of the fo...

    Text Solution

    |

  15. In a triangle ABC, if the sides are a=3, b=5, c=4, thenb the value of...

    Text Solution

    |

  16. The value of tan (7(1)/(2)) ^(@) is-

    Text Solution

    |

  17. If cos (x-y) =-1, then the values of (cos x+ cos y) and (sin x + sin y...

    Text Solution

    |

  18. If in a triangle ABC, b sin B = c sin C, then the triangle is-

    Text Solution

    |

  19. If (tan 3A)/(tan A)=x, then the value of (sin 3A)/(sin A) is-

    Text Solution

    |

  20. The locus of the centre of a circle which touches the circles |z-z(1)|...

    Text Solution

    |