Home
Class 12
MATHS
In triangle ABC, prove that 2(bc cos A +...

In `triangle ABC`, prove that `2(bc cos A +ac cos B +ab cos C)=a^2+b&2+c^2`.

Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC FUNCTIONS

    NAVNEET PUBLICATION - MAHARASHTRA BOARD|Exercise Multiple Choice Questions|12 Videos

  • TRIGONOMETRIC FUNCTIONS

    NAVNEET PUBLICATION - MAHARASHTRA BOARD|Exercise Theory Questions|1 Videos

  • THREE DIMENSIONAL GEOMETRY

    NAVNEET PUBLICATION - MAHARASHTRA BOARD|Exercise MULTIPLE CHOICE QUESTIONS|8 Videos

  • VECTORS

    NAVNEET PUBLICATION - MAHARASHTRA BOARD|Exercise Multiple choice question|10 Videos

Similar Questions

Explore conceptually related problems

In any ABC, prove that: 2(bosA+ca cos B+ab cos C)=a^(2)+b^(2)+c^(2)

2(bc cos A+ca cos B+ab cos C)=a^(2)+b^(2)+c^(2)

In triangle ABC , prove that (1) a=b cos C+c cos B (2) b=a cos C+c cos A .

In any triangle, ABC prove that: ac cos B-bc cos A=a^2-b^2

In any triangle ABC, prove that: a cos A+b cos B+c cos C=2a sin B sin C

For any triangle ABC, prove that (cos A)/(a)+(cos B)/(b)+(cos C)/(c)=(a^(2)+b^(2)+c^(2))/(2abc)

For any triangle ABC,prove that a(b cos C-c cos B)=b^(2)-c^(2)

In Delta ABC, prove that a^(2)+b^(2)+c^(2)=2(bc cos A+ca cos B+ab cos C)

For any triangle ABC,prove that a cos A+b cos B+c cos C=2a sin B sin C

In Delta ABC prove that a^(2)+b^(2)+c^(2)=2(bc cos A+ca cos B+ab cos C)

NAVNEET PUBLICATION - MAHARASHTRA BOARD-TRIGONOMETRIC FUNCTIONS -Examples for Practise
  1. In any DeltaABC, prove that (c-bcosA)/(b-c cos A)=(cos B)/(cosC)

    Text Solution

    |

  2. In triangle ABC , prove that (1) a=b cos C+c cos B (2) b=a cos C+c cos...

    Text Solution

    |

  3. In triangle ABC, prove that 2(bc cos A +ac cos B +ab cos C)=a^2+b&2+c^...

    Text Solution

    |

  4. In triangle ABC , prove that (b+c)cos A +(c+a)cos B +(a+b)cos C=a+b+c.

    Text Solution

    |

  5. In a A B C ,\ ifsin^2A+sin^2B=sin^2C , show that the triangle is righ...

    Text Solution

    |

  6. In triangle ABC, prove that a^2sin(B-C)=(b^2-c^2)sinA.

    Text Solution

    |

  7. In triangle ABC, prove that tan((C-A)/(2))=((c-a)/(c+a))cot(B)/(2).

    Text Solution

    |

  8. In triangle ABC , prove that (sin(A-B))/(sin(A+B))=(a^2-b^2)/(c^2).

    Text Solution

    |

  9. In triangle ABC, prove that b^2sin2C+c^2sin2B=2bcsinA.

    Text Solution

    |

  10. cos^2((B-C)/2)/((b+c)^2)+sin^2((B-C)/2)/((b-c)^2)=1/(a^2)

    Text Solution

    |

  11. If 2b=a+c, then prove that 3tan.(A)/(2).tan.(C)/(2)=1.

    Text Solution

    |

  12. In any triangle ABC, prove that a(cosB+cot(A/2).sinB)=b+c.

    Text Solution

    |

  13. In any triangle ABC, prove that a sin A-b sin B -=c sin (A-B).

    Text Solution

    |

  14. In triangle ABC, if angle C=(pi)/(2) , then prove sin(A-B)=(a^2-b^2)/(...

    Text Solution

    |

  15. In a triangle A B C , if acosA=bcosB , show that the triangle is eithe...

    Text Solution

    |

  16. In a triangle ABC, prove that cot(A/2)+cot(B/2)+cot(C/2)=((a+b+c)/(b+...

    Text Solution

    |

  17. In traingle ABC , prove that cos ((A-B)/(2))=((a+b)/(c)sin.(C)/(2).

    Text Solution

    |

  18. Find the principal of : (1) sin ^(-1)((1)/(2)) (2) tan^(-1)(-sqrt(3)...

    Text Solution

    |

  19. Find the values of : (1) cos^(-1)((1)/(2))+tan^(-1)((1)/sqrt(3)) (...

    Text Solution

    |

  20. Find the value of : (1) sin^(-1)(sin.(5pi)/(6)) (2) cos^(-1)(cos.(...

    Text Solution

    |