Home
Class 10
MATHS
If A, B and C are interior angles of a t...

If A, B and C are interior angles of a triangle ABC, then show that `"sin"((B+C)/2)=cosA/2` .

Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC IDENTITIES

    RD SHARMA ENGLISH|Exercise All Questions|254 Videos

Similar Questions

Explore conceptually related problems

If A, B and C are interior angles of a triangle ABC, then show that "sin"((B+C)/2)=cos(A/2) .

if A, B and C are interior angles of a triangle ABC, then show that cos((B+C)/2) = sin (A/2)

if A, B and C are interior angles of a triangle ABC, then show that cos((B+C)/2) = sin (A/2)

For triangle ABC, show that "sin"(A+B)/2="cos"C/2

If A ,\ B ,\ C are the interior angles of a triangle A B C , prove that tan(B+C)/2=cotA/2

If A, B and C are interior angles of a DeltaABC , then show that cot((B+C)/(2))=tan((A)/(2)) .

For triangle ABC, show that "tan"(B+C)/2="cot"A/2

If A ,\ B ,\ C are the interior angles of a triangle A B C , prove that tan((C+A)/2)=cotB/2 (ii) sin((B+C)/2)=cosA/2

For triangle ABC, show that: sin((A+B)/(2))-cos(C)/(2)=0

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

RD SHARMA ENGLISH-TRIGONOMETRIC RATIOS-All Questions
  1. Prove that: (cos80^@)/(sin10^@)+cos59^@\ cosec\ 31^@=2

    Text Solution

    |

  2. If sintheta=cos(theta-45^@) , where theta and theta-45^@ are acute a...

    Text Solution

    |

  3. If A, B and C are interior angles of a triangle ABC, then show that "s...

    Text Solution

    |

  4. If 2theta+45o and 30o-theta are acute angles, find the degree measu...

    Text Solution

    |

  5. If theta is a positive acute angle such that sectheta=cos e c\ 60o ...

    Text Solution

    |

  6. If cos2theta=sin4theta , where 2theta and 4theta are acute angles, ...

    Text Solution

    |

  7. If sin3theta=cos(theta-6^0), where (3theta)a n d(theta-6^0) are both...

    Text Solution

    |

  8. If s e c4A=cos e c(A-20^@) , where 4A is an acute angle, find the ...

    Text Solution

    |

  9. Write the maximum and minimum values of sintheta .

    Text Solution

    |

  10. Write the maximum and minimum values of costheta .

    Text Solution

    |

  11. What is the maximum value of 1/(sectheta) ?

    Text Solution

    |

  12. What is the maximum value of 1/(cos ec \ theta)?

    Text Solution

    |

  13. If tantheta=4/5, find the value of (costheta-sintheta)/(costheta+sinth...

    Text Solution

    |

  14. If costheta=2/3, find the value of (sectheta-1)/(sectheta+1) .

    Text Solution

    |

  15. If 3cottheta=4,find the value of (4costheta-sintheta)/(2costheta+sinth...

    Text Solution

    |

  16. Given tantheta=1/(sqrt(5)), what is the value of (cos e c^2theta-sec^2...

    Text Solution

    |

  17. If cottheta=1/(sqrt(3)) , show that (1-cos^2theta)/(2-sin^2theta)=3...

    Text Solution

    |

  18. If tanA=3/4 and A+B=90^@, then what is the value of cotB ?

    Text Solution

    |

  19. If A+B=90^@ and cosB=3/5 , what is the value of sinA ?

    Text Solution

    |

  20. Write the acute angle theta satisfying sqrt(3)sintheta=costheta .

    Text Solution

    |