Home
Class 10
MATHS
Prove that : "sin"(pi)/(3) "tan"(pi)/(6)...

Prove that : `"sin"(pi)/(3) "tan"(pi)/(6) +"sin"(pi)/(2) "cos"(pi)/(3) =2 "sin"^(2)(pi)/(4)`.

Text Solution

Verified by Experts

`LHS="sin"(pi)/(3) "tan"(pi)/(6) +"sin"(pi)/(2) "cos"(pi)/(3)`
`=sin60^(@) tan30^(@)+sin90^(@) cos60^(@)`
`=(sqrt(3))/(2) xx (1)/(sqrt(3)) + 1xx(1)/(2)=(1)/(2)+(1)/(2)=1`
`RHS=2 "sin"^(2)(pi)/(4) =2xx((1)/(sqrt(2)))^(2)=2xx(1)/(2)=1.`
`therefore LHS=RHS.` [Proved]
Promotional Banner

Topper's Solved these Questions

  • TRIGONOMETRIC RATIOS AND TRIGONOMETRIC IDENTITIES

    CALCUTTA BOOK HOUSE|Exercise EXERCISE|66 Videos
  • THEOREMS RELATED TO TANGENT IN A CIRCLE

    CALCUTTA BOOK HOUSE|Exercise EXERCISE 4.2|23 Videos
  • TRIGONOMETRIC RATIOS OF COMPLEMENTARY ANGLES

    CALCUTTA BOOK HOUSE|Exercise EXERCISE|28 Videos

Similar Questions

Explore conceptually related problems

"tan"^(2)(pi)/(4) "sin"(pi)/(3) "tan"(pi)/(6) "tan"^(2)(pi)/(3) =

Show that : "sin" 2(pi)/(7)+ "sin"(4pi)/(7)-"sin" (6pi)/(7) =4 "sin" (pi)/(7) "sin" (2pi)/(7) "sin" (3pi)/(7)

Evalute : "sin"^(2)(pi)/(4) + "cos"^(2) (3pi)/(4)+"cos"^(2)(5pi)/(4)+"sin"^(2)(7pi)/(4).

Prove that 3 sin ""pi/6 sec ""pi/3 -4 sin ""(5pi)/(6) cot"" (pi)/(4) =1

Prove that 2"sin"(5pi)/(12)"cos"(pi)/(12)=(sqrt3+2)/2

Prove that "sin"pi/5"sin"(2pi)/5"sin"(3pi)/5"sin"(4pi)/5=5/(16)

Prove that: sin^2(pi/(18))+sin^2(pi/9)+sin^2((7pi)/(18))+sin^2((4pi)/9)=2

Prove that sin (pi/14)sin((3pi)/14)sin((5pi)/14)=1/8

prove that "sin"^4pi/8+"sin"^4(3pi)/8+"sin"^4(5pi)/8+"sin"^4 (7pi)/8=3/2

sin ^(2)(pi/6) + cos ^(2)(pi/3) - tan ^(2)(pi/4) =- 1/2

CALCUTTA BOOK HOUSE-TRIGONOMETRIC RATIOS AND TRIGONOMETRIC IDENTITIES -EXERCISE
  1. Prove that : "sin"(pi)/(3) "tan"(pi)/(6) +"sin"(pi)/(2) "cos"(pi)/(3) ...

    Text Solution

    |

  2. If tan theta=(p)/(q), what is the value of (p sec theta-q " cosec" t...

    Text Solution

    |

  3. In DeltaABC, right angled at B, AB:AC=1:sqrt(2), then (2 tan A)/(1-ta...

    Text Solution

    |

  4. (sin30^(@)cos45^(@))/(tan 60^(@)) is equal to

    Text Solution

    |

  5. In DeltaABC, If angleC=90^(@), angleA=60^(@) and AB=40 cm, then AC is ...

    Text Solution

    |

  6. Write true of false : cot theta=(cos theta)/(sin theta)

    Text Solution

    |

  7. Write true of false : sin theta is a product of sin and theta.

    Text Solution

    |

  8. Fill in the blanks : The trigonometric ratio cos theta= ul(" ...

    Text Solution

    |

  9. Fill in the blanks : The value of sin theta can never be greate th...

    Text Solution

    |

  10. Fill in the blanks : The value of cot 0^(@) is not .

    Text Solution

    |

  11. Find the value of cos(-1170^(@)).

    Text Solution

    |

  12. Calculate the value of sec(-1680^(@)) sin 330^(@).

    Text Solution

    |

  13. Simplify : sin 300^(@) cos 390^(@) tan (-855^(@))+cos(-120^(@))* sin ...

    Text Solution

    |

  14. Prove that tan 225^(@) cot 405^(@)+tan 765^(@) cot 675^(@)=0.

    Text Solution

    |

  15. Evalute : "sin"^(2)(pi)/(4) + "cos"^(2) (3pi)/(4)+"cos"^(2)(5pi)/(4)...

    Text Solution

    |

  16. Prove that "tan"(pi)/(12) "tan"(pi)/(16) "tan"(5pi)/(12)"tan"(7pi)/(1...

    Text Solution

    |

  17. If tan 35^(@)=x, then prove that (tan 145^(@)- tan 125^(@))/(1+tan14...

    Text Solution

    |

  18. Find the value of sin^(3)60^(@) cot 30^(@)-2 sec^(2) 45^(@)+3 cos60^(@...

    Text Solution

    |

  19. If (cos theta)/(1-sin theta)-(costheta)/(1+sin theta)=2, then find the...

    Text Solution

    |

  20. If (cos x)/(cosy)=n and (sinx)/(siny)=m, what is the value of (m^(2)...

    Text Solution

    |

  21. If x cos 60^(@)+y cos0^(@)=3 and 4x sin 30^(@) -y cot 45^(@)=2, then ...

    Text Solution

    |