Home
Class 12
MATHS
Let alpha=pi//12 , and E=(1+cos alpha)(1...

Let `alpha=pi//12 , and E=(1+cos alpha)(1+cos(3alpha))(1+cos(5alpha))(1+cos(7alpha))(1+cos(9alpha))(1+cos(11alpha))`
Then `8E=` ______

Text Solution

Verified by Experts

The correct Answer is:
`0.25`
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRICAL IDENTITIES AND EQUATIONS

    MCGROW HILL PUBLICATION|Exercise Questions from Previous Years. AIEEE/JEE Main Papers|48 Videos

  • TRIGONOMETRICAL IDENTITIES AND EQUATIONS

    MCGROW HILL PUBLICATION|Exercise Questions from Previous Years. B-Architecture Entrance Examination Papers|20 Videos

  • TRIGONOMETRICAL IDENTITIES AND EQUATIONS

    MCGROW HILL PUBLICATION|Exercise EXERCISE (LEVEL 2 Single Correct Answer Type Questions)|30 Videos

  • THE DIMENSIONAL GEOMETRY

    MCGROW HILL PUBLICATION|Exercise QUESTIONS FROM PREVIOUS YEARS. B-ARCHITECTURE ENTRANCE EXAMINATION PAPERS|25 Videos

  • VECTOR ALGEBRA

    MCGROW HILL PUBLICATION|Exercise QUESTIONS FROM PREVIOUS YEARS. B-ARCHITECTURE ENTRANCE EXAMINATION PAPERS|20 Videos

Similar Questions

Explore conceptually related problems

cos4 alpha=1-8cos^(2)alpha+8cos^(4)alpha

(1)/(cos alpha+cos3 alpha)+(1)/(cos alpha+cos5 alpha)...(.1)/(cos alpha+cos(2n+1)alpha)

(sin alpha)/(1+cos alpha)+(1+cos alpha)/(sin alpha)=2cosec alpha

If alpha=22^(@)30'then(1+cos alpha)(1+cos3 alpha)(1+cos5 alpha)(1+cos7 alpha) equals

If alpha=(pi)/(17), show that (cos alpha cos13 alpha)/(cos3 alpha+cos5 alpha)=-(1)/(2)

(1+sin alpha)/(1+cos alpha)*(1+sec alpha)/(1+cos ec alpha)=tan alpha

cos alpha*cos60-alpha*cos60+alpha-(1)/(4)cos3 alpha

MCGROW HILL PUBLICATION-TRIGONOMETRICAL IDENTITIES AND EQUATIONS -EXERCISE (Numerical Answer Type Questions)
  1. 4 sin((pi)/(18))sin((5pi)/(18))sin((7pi)/(18))=

    Text Solution

    |

  2. If cot (theta-alpha) cot(theta-beta)=cot^(2) theta, then 2(1+cot(2the...

    Text Solution

    |

  3. If alpha=(pi)/(28), and a=(sin alpha)/(cos(3alpha))+(sin (3alpha))/(c...

    Text Solution

    |

  4. Let alpha=pi//12 , and E=(1+cos alpha)(1+cos(3alpha))(1+cos(5alpha))(1...

    Text Solution

    |

  5. Suppose f(theta)=cos theta cos(2theta) cos(2^(2) theta)-cos(2^(n) t...

    Text Solution

    |

  6. For theta in R, let f(theta)=cos^(2)theta+cos^(2)(theta+pi//6)+sin...

    Text Solution

    |

  7. Let a(n)=sum(k=1)^(n)tan^(-1)((2^(k))/(2+4^(k))), then tan(a(oo)-a(2))...

    Text Solution

    |

  8. If (sin^(2)x)/(1+sin^(2)x)+(cos^(2)x)/(1+cos^(2)x)=2+(k)/(cos(4x)-17) ...

    Text Solution

    |

  9. (tan 10^(@)+tan 70^(@)-tan50^(@))^(2)= .

    Text Solution

    |

  10. tan^(6)((pi)/(9))-33 tan^(4)((pi)/(9))+27tan^(2)((pi)/(9))= .

    Text Solution

    |

  11. Let f(x)=cos^(2)((pi)/(4)+x)+(sinx-cosx)^(2), AA x in R then max(f(x))...

    Text Solution

    |

  12. Let M = the maximum value of (1)/(9 sin^(2)x+24 sin x cosx+19cos^(2...

    Text Solution

    |

  13. Let alpha=(1)/(8) sum(k=0)^(10)sec((7pi)/(12)+(kpi)/(2)) sec((7pi)/(12...

    Text Solution

    |

  14. Suppose for 0 lt x lt (pi)/(2), (sin(7x))/(sinx)=a cos(6x)+b cos(4x)+c...

    Text Solution

    |

  15. If x in [0, 2pi], then the number of solutions of sin^(5)x-cos^(5)x=(1...

    Text Solution

    |

  16. If x in [0, 2pi], then the number of solutions of sin^(3)x+cos^(3)x=1,...

    Text Solution

    |

  17. If x in [0, 2pi], then the number of solutions of 4-4(cosx-sin x)-sin2...

    Text Solution

    |

  18. The number of solutions of 2(cosx+cos(2x))+sin(2x)(1+2cosx)=2sinx lyin...

    Text Solution

    |

  19. The number of solutions of tanx tan(x+pi//3)tan(x+2pi//3)= -1 lying...

    Text Solution

    |

  20. The number of values of x in (0, 2pi) satisfying the equation |cosx|^(...

    Text Solution

    |