Home
Class 11
MATHS
If A+B+C=pi, prove that: "sin" A+"sin...

If` A+B+C=pi`, prove that:
`"sin" A+"sin" B-"sin" C=4 "sin"(A)/(2)"sin"(B)/(2)"cos"(C)/(2)`.

Text Solution

AI Generated Solution

Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise NCERT EXAMPLES|6 Videos

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise Exercise 3(a) Short Answer type Question|13 Videos

  • TRIGONOMETRY

    MODERN PUBLICATION|Exercise Chapter Test (3)|12 Videos

  • STRAIGHT LINES

    MODERN PUBLICATION|Exercise Chapter test|12 Videos

Similar Questions

Explore conceptually related problems

sin A + sin B-sin C = 4sin ((A) / (2)) sin ((B) / (2)) cos ((C) / (2))

If A+B+C=pi , prove that sin 2A+sin 2B-sin 2C=4 cos A cos B sin C

If A+B+C=pi , prove that : sin2A+sin2B+sin2C=4sinA sinB sinC

If A+B+C=pi , prove that sin 2A-sin 2B+sin 2C=4cos Asin B cos C.

If A+B+C =pi , prove that sin 2A+sin 2B+sin 2C=4 sin Asin B sin C.

If A+B+C=pi, prove that sin2A-sin2B+sin2C=4cosA sin B cosC .

If A+B+C=180^@ prove that sin A+sin B+sin C=4 "cos" A/2 "cos" B/2 "cos" C/2

Theorem 4:sin A+sin B+sin C=4(cos A)/(2)(cos B)/(2)(cos C)/(2)

sin A + sin B + sin C = 4cos ((A) / (2)) cos ((B) / (2)) cos ((C) / (2))

If A+B+C=pi then prove that cos A+cos B+cos C=1+4sin((A)/(2))*sin((B)/(2))*sin((C)/(2))

MODERN PUBLICATION-TRIGONOMETRY-FREQUENTLY ASKED QUESTIONS
  1. If A+B+C=pi, the value of sin2A+sin2B+sin2C=ksinAsinBsinC then value o...

    Text Solution

    |

  2. If A+B+C=pi , prove that cos 2A +cos 2B +cos 2C=-1-4cos A cos Bcos ...

    Text Solution

    |

  3. If A+B+C=pi, prove that: "sin" A+"sin" B-"sin" C=4 "sin"(A)/(2)"sin...

    Text Solution

    |

  4. Prove that: ("sin"(x+theta))/("sin"(x+varphi))=cos(theta-varphi)+cot(x...

    Text Solution

    |

  5. If 0+phi=45^(@),prove that: (1+"tan" theta)(1+"tan" phi)=2.

    Text Solution

    |

  6. Prove that tan 56^@ = (cos11^@ + sin11^@)/(cos11^@ - sin11^@)

    Text Solution

    |

  7. Prove that: "tan"3 theta tan 2theta tan theta="tan" 3theta-"tan" 2t...

    Text Solution

    |

  8. Prove that: (cos^2 33^0-cos^2 57^0)/(sin^2(21^0)/2-sin^2(69^0)/2)=-sqr...

    Text Solution

    |

  9. Prove that tan 70^(@) = "tan " 20^(@) + 2"tan " 50^(@)

    Text Solution

    |

  10. Prove that sin(A+B)sin(A-B)=sin^2A-sin^2B=cos^2B-cos^2A

    Text Solution

    |

  11. If 2tanbeta+cotbeta=tanalpha , prove that cotbeta=2tan(alpha-beta)dot

    Text Solution

    |

  12. If tan n = (1)/(sqrt (x (x ^(2) + x + 1))). tan beta = (sqrtx)/(sqrt (...

    Text Solution

    |

  13. If "tan"(alpha+theta)=n "tan"(alpha-theta),ahow that: (n+1)"sin"2 t...

    Text Solution

    |

  14. If tan(picostheta)=cot(pisintheta), then cos(theta-(pi)/(4))=pm(1)/(2s...

    Text Solution

    |

  15. If "sin" theta=(3)/(5),cos phi=-(12)/(13), where theta and phi both li...

    Text Solution

    |

  16. If A and B are positive acute angles and cos A = 1/7, cos B = 13/14, t...

    Text Solution

    |

  17. Find the maximum and minimum values of 7costheta + 24sintheta

    Text Solution

    |

  18. Prove that 5costheta+3cos(theta+pi/3)+3 lies between -4a n d10.

    Text Solution

    |

  19. Prove that: cos 2theta"cos"(theta)/(2)-cos 3theta cos((9theta)/2)="...

    Text Solution

    |

  20. Prove that (2cos2A+1)/(2cos2A-1)=tan(60^0+A)tan(60^0-A)dot

    Text Solution

    |