Home
Class 11
MATHS
If 3 tan theta tan phi=1, then prove tha...

If `3 tan theta tan phi=1`, then prove that 2 `cos (theta+varphi)=cos (theta-varphi)`.

Promotional Banner

Topper's Solved these Questions

  • STRAIGHT LINES

    CENGAGE ENGLISH|Exercise All Questions|491 Videos

Similar Questions

Explore conceptually related problems

If 3 tan theta tan phi=1 , then prove that 2 cos (theta+phi)=cos (theta-phi) .

If 3 tan theta tan phi=1, then (cos (theta-phi))/(cos (theta+phi)) is

If 3 tan theta tan phi=1, then (cos (theta-phi))/(cos (theta+phi)) is

If tan^2 theta = 1+2 tan^2 phi , prove that cos 2 phi = 1 + 2 cos 2 theta .

If t a n^2theta=2tan^2phi+1 , prove that cos2theta+sin^2phi=0.

If sin theta + cos theta =sqrt(3), then prove that tan theta + cot theta = 1 .

If tan theta tan phi=sqrt((a-b)/(a+b)) , prove that a-bcos 2theta)(a-b cos 2phi) is independent of theta and phi .

If sin2theta+sin2varphi=1/2a n d\ cos2theta+cos2varphi=3/2 , then cos^2(theta-varphi)= a. 3//8 b. 5//8 c. 3//4 d. 5//4

If 0 lt theta , phi lt pi and 8 cos theta cos phi cos (theta + phi)+1=0 find theta and phi

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

CENGAGE ENGLISH-TRIGONOMETRIC FUNCTIONS-All Questions
  1. One value of theta which satisfies the equation sin^(4)theta-2sin^(2)t...

    Text Solution

    |

  2. If A=sin^(8) theta + cos^(14) theta, then for all values of theta,

    Text Solution

    |

  3. If 3 tan theta tan phi=1, then prove that 2 cos (theta+varphi)=cos (th...

    Text Solution

    |

  4. Minimum value of y=256sin^2x+324cos e c^2x,AAx in R is (a) 432 (b) 5...

    Text Solution

    |

  5. If (cos^2x+1/(cos^2x)) (1+tan^2 2y)(3+sin3z)=4, then x is an integral ...

    Text Solution

    |

  6. A circle is inscribed in a triangle A B C touching the side A B at D s...

    Text Solution

    |

  7. In a triangle ABC, if sinAsin(B-C)=sinCsin(A-B), then prove that cotA...

    Text Solution

    |

  8. The minimum value of the expression sin alpha + sin beta+ sin gamma, ...

    Text Solution

    |

  9. In A B C ,cotA/2+cotB/2+cotC/2 is equal to Delta/(r^2) (b) ((a+b+...

    Text Solution

    |

  10. The value of theta in (0,2pi) for which 2sin^2theta-5sintheta+2>0 is (...

    Text Solution

    |

  11. In A B C , if cotA+cotB+cotC=0 then find the value of cosAcos BcosC

    Text Solution

    |

  12. Show that tan1^0tan2^0tan89^0=1

    Text Solution

    |

  13. In triangle ABC, the line joining the circumcenter and incenter is p...

    Text Solution

    |

  14. The number of solutions of the pair of equations 2sin^2 theta - cos(2 ...

    Text Solution

    |

  15. Given A=sin^2theta+cos^4theta, then for all real theta, (a)1lt=Alt...

    Text Solution

    |

  16. If A ,B ,C ,D are angles of a cyclic quadrilateral, then prove that c...

    Text Solution

    |

  17. The number of distinct real roots of |sinxcosxcosxcosxsinxcosxcosxcosx...

    Text Solution

    |

  18. D , E ,a n dF are the middle points of the sides of the triangle A B C...

    Text Solution

    |

  19. If cos(A-B)=3/5 and tan A tan B=2, then (a) cos Acos B=1/5 (b) sin A ...

    Text Solution

    |

  20. The number of ordered pairs (α,β), where α,β∈(−π,π) satisfying cos (α−...

    Text Solution

    |