Home
Class 11
MATHS
cos 10x + cos 8x + 3 cos 4x + 3 cos 2x=...

`cos 10x + cos 8x + 3 cos 4x + 3 cos 2x=`

A

`8 cos x cos 3x`

B

`8 cos ^(3) x+ cos 3x`

C

`8 cos^(3) x cos ^(3) x`

D

`8 cos x cos ^(3) 3x`

Text Solution

Verified by Experts

The correct Answer is:
D
Promotional Banner

Topper's Solved these Questions

  • FACTORIZATION FORMULAE

    TARGET PUBLICATION|Exercise COMETITIVE THINKING|34 Videos

  • FACTORIZATION FORMULAE

    TARGET PUBLICATION|Exercise EVALUATION TEST|8 Videos

  • FACTORIZATION FORMULAE

    TARGET PUBLICATION|Exercise EVALUATION TEST|8 Videos

  • CIRCLE AND CONICS

    TARGET PUBLICATION|Exercise EVALUATION TEST|28 Videos

  • PROBABILITY

    TARGET PUBLICATION|Exercise EVALUATION TEST|8 Videos

Similar Questions

Explore conceptually related problems

Prove that 1 + cos 2x + cos 4x + cos 6x = 4 cos x *cos 2x *cos 3x .

Prove that 2cosx. Cos 3x- 2cos 5x. Cos 7x- cos 4x + cos12x=0 .

int ((cos 6x+6cos 4x+ 15 cos 2x+10)/(10 cos ^(2) x +5 cos x cos 3 x+ cos x cos 5 x ))dx =f (x)+C, then f (10) is equal to:

(" sin 8x cos x- sin 6x cos 3x")/(" cos 2x cos x - sin 4x sin 3x")=

cos x cos 2x cos 4x cos 8x =(sin 16x)/(16sin x)

cos ec2x + cos ec4x + cos ec8x + cos ec16x

TARGET PUBLICATION-FACTORIZATION FORMULAE-CRITICAL THINKING
  1. Find the value of cos 12^(@)+cos 84^(@)+cos 156^(@)+cos 132^(@)

    Text Solution

    |

  2. The value of cot 70^(@) + 4 cos 70^(@) is

    Text Solution

    |

  3. cos 10x + cos 8x + 3 cos 4x + 3 cos 2x=

    Text Solution

    |

  4. 1+ cos 2x+ cos4x + cos 6x=

    Text Solution

    |

  5. The expression (cos 6x+6cos 4x+15 cos 2x+10)/(cos 5x+5 cos 3x+10 co...

    Text Solution

    |

  6. If sin theta+sin2theta+sin3theta=sin alpha and cos theta+cos 2theta+co...

    Text Solution

    |

  7. If cosx+cosy+cosalpha=0 and sinx+siny+sinalpha=0 then cot((x+y)/2)=

    Text Solution

    |

  8. (cos A+ cos B) ^(2) + (sin A-sin B) ^(2) is equal to

    Text Solution

    |

  9. cos ^(2) alpha + cos ^(2) (alpha + 120^(@)) + cos ^(2) (alpha - 120^(@...

    Text Solution

    |

  10. If (" cos " (A+B))/(" cos " (A-B)) =(" sin " (C+D))/(" sin " (C -D))...

    Text Solution

    |

  11. (sin^2A- sin^2B)/( sin A cos A-sin Bcos B) =tan(A+B)

    Text Solution

    |

  12. The value of cos""(pi)/(11)+cos""(3pi)/(11)+cos""(5pi)/(11)+cos""(7pi)...

    Text Solution

    |

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

    Text Solution

    |

  14. The value of sin ""(pi)/(16) sin ""(3pi)/(16) sin ""(5pi)/(16) sin ""(...

    Text Solution

    |

  15. sin 20^(@) sin 40^(@) sin 60^(@) sin 80^(@) =

    Text Solution

    |

  16. Prove that tan 20^(@) tan 40^(@) tan 80^(@)=tan 60^(@)

    Text Solution

    |

  17. The value of (tan 70^(@) - tan 20^(@))/( tan 50^(@))=

    Text Solution

    |

  18. The value of tan20^(@)+2 tan50^(@)-tan70^(@), is

    Text Solution

    |

  19. cosec 48^(@) + cosec 96^(@) + cosec 192^(@) + cosec 384^(@)=

    Text Solution

    |

  20. If the value of cos((2pi)/7) + cos((4pi)/7)+cos((6pi)/7)+cos((7pi/7))=...

    Text Solution

    |