Home
Class 12
MATHS
If A+B+C=pi then the value of cos ^(2)A ...

If `A+B+C=pi` then the value of `cos ^(2)A + cos ^(2) B+ cos ^(2)C` is-

A

`1-cos A cos B cosC`

B

`2 cos A cos B cos C`

C

`1-2 cos A cos B cos C`

D

`1+2 cos A cos B cos C`

Text Solution

Verified by Experts

The correct Answer is:
C
Promotional Banner

Topper's Solved these Questions

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 6|90 Videos

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 9|66 Videos

  • MCQ's

    CHHAYA PUBLICATION|Exercise QUESTION PAPER 7|90 Videos

  • MCQ ZONE 3

    CHHAYA PUBLICATION|Exercise Question Paper 8|30 Videos

  • Measures of Central Tendency

    CHHAYA PUBLICATION|Exercise Exercise 2 C Very short answer type question|18 Videos

Similar Questions

Explore conceptually related problems

If A+C+B=180, then the value of (cos ^(2) A+ cos ^(2) B +cos ^(2) C-2 cos A cos B cos C) is-

If ABC is a right angled triangle, then the value of (cos ^(2)A +cos ^(2) B+ cos ^(2)C) is -

If A+B+C=270^(@), then the value of cos 2A +cos 2B + cos 2C + 4 sin A sin B sin C is-

If A+C=2b, then the value of (cos C - cos A)/(sin A-sin C) is-

In any triangle ABC, the valur of a (cos ^(2) B+ cos ^(2)C)+ cos A (b cos B+ c cos C) is-

Find the value of 2cos^3(pi/7)-cos^2(pi/7)-cos(pi/7)

Let ABC be an acute angled triangle with orthocenter H.D, E, and F are the feet of perpendicular from A,B, and C, respectively, on opposite sides. Also, let R be the circumradius of DeltaABC . Given AH.BH.CH = 3 and (AH)^(2) + (BH)^(2) + (CH)^(2) = 7 Then answer the following Value of (cos A. cos B . cos C)/(cos^(2)A + cos^(2)B + cos^(2)C) is

If cot^2Acot^2B=3, then the value of (2-cos2A)(2-cos2B) is ____

If A,B,C are the angles of a triangle, prove that the maximum value of cos A cos B cos C "is" (1)/(8)

If in a triangle ABC, cos^(2)A + cos^(2)B + cos^(2)C =1 , then show that the triangle is right angled.

CHHAYA PUBLICATION-MCQ's-QUESTION PAPER 8
  1. If x= sum(n=0)^(oo) cos ^(2n)theta , y = sum (n=o) ^(oo) sin ^(2n)thet...

    Text Solution

    |

  2. In a triangle PQR, angle R=(pi)/(2). If tan ""P/2 and tan ""Q/2 are th...

    Text Solution

    |

  3. If A+B+C=pi then the value of cos ^(2)A + cos ^(2) B+ cos ^(2)C is-

    Text Solution

    |

  4. Find the value of sin^(2)5^(@)+sin^(2)10^(@)+sin^(2)15^(@)+..............

    Text Solution

    |

  5. If a,b, c are in G. P. then ((1)/(a ^(2) -b^(2))+ (1)/(b^(2))) is equl...

    Text Solution

    |

  6. If the amplitude of (z-2 -3i) is pi/4, then the locus of z=x +iy is -

    Text Solution

    |

  7. A fair coin is tossed 10 times. The probability of getting exactly 6 h...

    Text Solution

    |

  8. The value of [""^(47)C(4) +sum (r=1)^(5) ""^(52-r)C(3)] is equal to-

    Text Solution

    |

  9. If 1, omega, omega ^(2) are the cube roots of unity, then the value of...

    Text Solution

    |

  10. Let l(1) and l(2) be thw two lines intersecting at P. If A(1), B(1), C...

    Text Solution

    |

  11. Three numbers are chosen at random from the first 20 natural numbers. ...

    Text Solution

    |

  12. The first term of an infinite G.P. is a and its sum is 3, then-

    Text Solution

    |

  13. If a(1) =2 and for all n ge 2, a(n)-a(n-1)=2n, then the value of (a(1...

    Text Solution

    |

  14. If the coefficient of x^(3) in the expansion of (x^(2) + (k)/(x))^(6) ...

    Text Solution

    |

  15. If sqrt(a+ib) =x+iy then possible value of sqrt(a-ib) is-

    Text Solution

    |

  16. A student is to answer 10 out of 13 questions in an examination such t...

    Text Solution

    |

  17. The median of a distribution is 60 and mean deviation about median is ...

    Text Solution

    |

  18. If omega is a complex cube root of unity then the value of [225 + ( 3 ...

    Text Solution

    |

  19. Seventh term of an A.P. ios 40. Then the sum of its first 13 items is-

    Text Solution

    |

  20. If x = sum (n =0) ^(oo) a^(n) , y = sum (n=0) ^(oo) b ^(n), z= sum (n=...

    Text Solution

    |