Home
Class 11
MATHS
For any triangle ABC, If B=3C, show tha...

For any triangle ABC, If `B=3C`, show that `cosC=sqrt((b+c)/(4c)) and sinA/2=(b-c)/(2c)`

Promotional Banner

Topper's Solved these Questions

  • BASIC MATHS,LOGARITHIM, TRIGNOMETRIC RATIO AND IDENTITIES AND TRIGNOMETRIC EQUATION

    ALLEN|Exercise EXERCISE (S-1)|44 Videos

  • Solutions of Triangle & Binomial Theorem

    ALLEN|Exercise Do yourself -6|4 Videos

Similar Questions

Explore conceptually related problems

For any triangle ABC, If B=3C, show that cos C=sqrt((b+c)/(4c)) and (sin A)/(2)=(b-c)/(2c)

In any triangle ABC,show that: 2a cos((B)/(2))cos((C)/(2))=(a+b+c)sin((A)/(2))

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

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

In any triangle ABC, show that: 2a sin((B)/(2))sin((C)/(2))=(b+c-a)sin((A)/(2))

In a triangle ABC , acosB + b cosC + c cosA =(a+b+c)/2 then

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

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

If Delta ABC,quad if (cos A)/(2)=sqrt((b+c)/(2c)), then

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

ALLEN-SOLUTION AND PROPERTIES OF TRIANGLE-All Questions
  1. Prove that : 4\ R\ sin AsinB\ sin C=acosA+b\ cos B+c cosCdot

    Text Solution

    |

  2. If p1,\ p2, p3 are the altitudes of a triangle from the vertices A , B...

    Text Solution

    |

  3. For any triangle ABC, If B=3C, show that cosC=sqrt((b+c)/(4c)) and s...

    Text Solution

    |

  4. A B C is a triangle. D is the mid point of B Cdot If A D is perpendicu...

    Text Solution

    |

  5. Prove that r1+r2+r3-r=4R

    Text Solution

    |

  6. In a Delta ABC, GA,GB,GC makes angles alpha, beta, gamma with each oth...

    Text Solution

    |

  7. In a DeltaABC, the median to the side BC is of length 1/sqrt(11-6sqrt...

    Text Solution

    |

  8. Prove that : (r1)/(b c)+(r2)/(c a)+(r3)/(a b)=1/r-1/(2R)

    Text Solution

    |

  9. Prove that : (tanA/2)/((a-b)(a-c))+(tanB/2)/((b-a)(b-c))+(tanC/2)/((c-...

    Text Solution

    |

  10. Prove that in a triangle (b c)/(r1)+(c a)/(r2)+(a b)/(r3)=2R\ [(a/b+b...

    Text Solution

    |

  11. In a triangle, if the angles A , B ,a n dC are in A.P. show that 2cos1...

    Text Solution

    |

  12. In a scalene triangle ABC the altitudes AD & CF are dropped from the v...

    Text Solution

    |

  13. Let a, b, c be the sides of a triangle & Delta its area. Prove that a^...

    Text Solution

    |

  14. If in a triangle of base 'a', the ratio of the other two sides is r ( ...

    Text Solution

    |

  15. If Delta is the area of a triangle with side lengths a, b, c, then s...

    Text Solution

    |

  16. Which of the following pieces of data does NOT uniquely determine an ...

    Text Solution

    |

  17. If a ,b ,c are the sides of a triangle such that a : b : c=1:sqrt(3...

    Text Solution

    |

  18. If a ,b ,c denote the lengths of the sides of a triangle opposite t...

    Text Solution

    |

  19. One angle of an isosceles triangle is 120^0 and the radius of its incr...

    Text Solution

    |

  20. Internal bisector of /A of triangle ABC meets side BC at D. A line dra...

    Text Solution

    |