Home
Class 11
MATHS
If 8cos2theta+8sec2theta=65,0ltthetaltpi...

If `8cos2theta+8sec2theta=65`,`0ltthetaltpi/2`, then the value of `4cos4theta` is equal to

A

`-(33)/(8)`

B

`-(31)/(8)`

C

`-(31)/(32)`

D

`-(33)/(32)`

Text Solution

Verified by Experts

The correct Answer is:
B
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES

    TARGET PUBLICATION|Exercise EVALUATION TEST|12 Videos

  • TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES

    TARGET PUBLICATION|Exercise CRITICAL THINKING|60 Videos

  • STRAIGHT LINE

    TARGET PUBLICATION|Exercise EVALUATION TEST|10 Videos

  • TRIGONOMETRIC FUNCTIONS

    TARGET PUBLICATION|Exercise EVALUATION TEST|10 Videos

Similar Questions

Explore conceptually related problems

If 8cos2 theta+8sec2 theta=65,0

If 8 cos 2 theta + 8 sec 2theta = 65, 0 lt theta lt (pi)/(2) then the value of 4 cos 4 theta is

If 8cos2theta+8sec2theta=65and0^(@)ltthetalt(pi)/(2) , then 4cos4theta is equal to

If 8cos^(2)theta+8sec^(2)theta=65 and 0^(@)

If cos theta + sec theta = 2 ( 0^@ letheta le 90^@) , then the value of cos 10 theta + sec 11 theta is

If 5cos2theta+2"cos"^(2)(theta)/(2)+1=0 , when (0ltthetaltpi) , then the values of theta are

If cos theta+sec theta=-2,theta in[0,2 pi] then sin^(8)theta+cos^(8)theta is equal to

If sin theta+cos ec theta=2, then the value of sin^(8)theta+cos ec^(8)theta is equal to

TARGET PUBLICATION-TRIGONOMETRIC FUNCTIONS OF COMPOUND ANGLES -COMPETITIVE THINKING
  1. If cot ""(2x)/(3) + tan (x/3) = cosec (kx)/(3), then the value of k is

    Text Solution

    |

  2. If 2 sin^(2) ((pi//2) cos^(2) x)=1-cos (pi sin 2x), x ne (2n + 1) pi//...

    Text Solution

    |

  3. If 8cos2theta+8sec2theta=65,0ltthetaltpi/2, then the value of 4cos4the...

    Text Solution

    |

  4. If 5(tan^2x - cos^2x)=2cos 2x + 9, then the value of cos4x is

    Text Solution

    |

  5. x+1/x=2cosalpha then x^n+1/x^n=

    Text Solution

    |

  6. If sin x + cos x = 1/5, then tan 2x is

    Text Solution

    |

  7. If A lies in the third quadrant and 3 tan A-4 = 0, then 5 sin 2A + 3si...

    Text Solution

    |

  8. If a tan theta = b, then a cos 2 theta+ b sin 2 theta =

    Text Solution

    |

  9. If a cos 2 theta + b sin 2 theta =c has alpha and beta as its solut...

    Text Solution

    |

  10. If alpha, beta are solutin of 6 cos theta + 8 sin theta=9, then sin (...

    Text Solution

    |

  11. If alpha is a root of 25cos^2theta+5costheta-12=0,pi/2ltalphaltpi the ...

    Text Solution

    |

  12. 2 cos ^(2) theta - 2 sin ^(2) theta =1, then theta =

    Text Solution

    |

  13. 2 sin A cos ^(3) A-2 sin ^(3) A cos A=

    Text Solution

    |

  14. sin^4\ pi/8 + sin^4\ (3pi)/8 + sin^4\ (5pi)/8 + sin^4\ (7pi)/8=

    Text Solution

    |

  15. 3(sin x- cos x )^(4) + 6(sin x+ cos x )^(2) +4 (sin ^(6) x+ cos ^(6) x...

    Text Solution

    |

  16. If sin 2 theta + sin 2 phi =1/2 and cos 2 theta + cos 2 phi =3/2, then...

    Text Solution

    |

  17. If n=1,2,3,......., then cosalphacos2alphacos4alpha.......cos2^(n-1)a...

    Text Solution

    |

  18. cos ""(2pi)/( 15) cos ""(4pi)/(15) cos ""(8pi)/(15) cos ""(16pi)/(15)=

    Text Solution

    |

  19. If K=sin(pi/(18))sin((5pi)/(18))sin((7pi)/(18)), then the numerical va...

    Text Solution

    |

  20. The value of sinpi/(14)sin(3pi)/(14)sin(5pi)/(14)sin(7pi)/(14)sin(9pi)...

    Text Solution

    |