Home
Class 11
MATHS
(1+"cos"(pi)/8)(1+"cos"(3pi)/8)(1+"cos"(...

`(1+"cos"(pi)/8)(1+"cos"(3pi)/8)(1+"cos"(5pi)/8)(1+"cos"(7pi)/8)=`

A

`1/8`

B

`1/2`

C

`1/(sqrt(3))`

D

`1/(sqrt(2))`

Text Solution

Verified by Experts

The correct Answer is:
A
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRY

    NCERT TAMIL|Exercise EXERCISE 3.11|5 Videos

  • TRIGONOMETRIC FUNCTIONS

    NCERT TAMIL|Exercise MISCELLANEOUS EXAMPLES|10 Videos

  • TWO DIMENSIONAL ANALYTICAL GEOMETRY

    NCERT TAMIL|Exercise EXERCISE 6.5 (Choose the correct or more suitable answer)|25 Videos

Similar Questions

Explore conceptually related problems

Show that "cos"(pi)/(15)"cos"(2pi)/(15)"cos"(3pi)/(15)"cos"(4pi)/(15)"cos"(5pi)/(15)"cos"(6pi)/(15)"cos"(7pi)/(15)=(1)/(128) .

The value of (1+cospi/8)(1+cos(3pi)/8)(1+cos(5pi)/8)(1+cos(7pi)/8)i s (a)1/4 (b) 3/4 (c) 1/8 (d) 3/8

Show that cos (pi)/(15) cos""(2pi)/(15) cos"" (3pi)/(15) cos"" (4pi)/(15) cos"" (5pi)/(15) cos"" (6pi)/(15) cos"" (7pi)/(15) = (1)/(128) .

The value of cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)/(11)+cos""(9pi)/(11), is

Prove that 32 (sqrt(3)) sin"" (pi)/(48) cos"" (pi)/(48) cos"" (pi)/(24) cos"" (pi)/(12) cos"" (pi)/(6) = 3

Prove that 2 cos""(pi)/(13)cos""(9pi)/(13)+cos""(3pi)/(13)+cos""(5pi)/(13)=0

cos""(2pi)/(15)cos""(4pi)/(15)cos""(8pi)/(15)cos""(16pi)/(15)=(1)/(16)

Prove that cos^(2)""pi/8+cos^(2) ""(3pi)/(8)+cos^(2)""(5pi)/(8)+cos^(2)""(7pi)/(8)=2

NCERT TAMIL-TRIGONOMETRY-EXERCISE 3.12
  1. 1/(cos 80^(@))-(sqrt(3))/(sin80^(@))=

    Text Solution

    |

  2. If cos 28^(@)+sin28^(@)=k^(3) then cos 17^(@) is equal to

    Text Solution

    |

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

    Text Solution

    |

  4. (1+"cos"(pi)/8)(1+"cos"(3pi)/8)(1+"cos"(5pi)/8)(1+"cos"(7pi)/8)=

    Text Solution

    |

  5. If pilt 2 theta lt (3pi)/2 then sqrt(2+sqrt(2+24theta) equals to

    Text Solution

    |

  6. If tan 40^(@)=lamda then (tan 140^(@)-tan 130^(@))/(1+tan 140^(@)tan 1...

    Text Solution

    |

  7. cos1^(@)+cos2^(@)+cos3^(@)+…………..+cos 179^(@)=

    Text Solution

    |

  8. Let f(x)(x)=1/k[sin^(k)x+cos^(k)x] where x in R and kge1. Then f(4)(x)...

    Text Solution

    |

  9. Which of the following is not true?

    Text Solution

    |

  10. cos 2 theta cos 2 phi +sin^(2)(theta-phi)-sin^(2)(theta+phi) is equal ...

    Text Solution

    |

  11. (sin(A-B))/(cosAcosB)+(sin(B-C))/(cosBC)+(sin(C-A))/(cosCcosA) is

    Text Solution

    |

  12. If cos p theta+cos q theta=0 and if p!=q, then theta is equal to (n is...

    Text Solution

    |

  13. If tan alpha and tan beta are the roots of x^(2)+ax+b=0 then (sin (alp...

    Text Solution

    |

  14. In a triangle ABC sin^(2)A+sin^(2)B+sin^(2)B+sin^(2)C=2, then the tria...

    Text Solution

    |

  15. If f(theta)=|sin theta|+|cos theta|, theta in R then f(theta) is the i...

    Text Solution

    |

  16. (cos 6x+6cos 4x+15cos 2x+10)/(cos 5x+5cos3x+10cosx) is equal to

    Text Solution

    |

  17. The triangle of maximum area with constant perimeter 12 m

    Text Solution

    |

  18. A wheel is spinnig at 2 radians/second. How many seconds will it take ...

    Text Solution

    |

  19. If sin alpha+cos alpha=b then sin 2 alpha is equal to

    Text Solution

    |

  20. In a DeltaABC if (i) "sin"A/2"sin"B/2"sin"C/2gt0 (ii) sinAsinBsinC...

    Text Solution

    |