Home
Class 12
MATHS
If in A B C ,A=pi/7,B=(2pi)/7,C=(4pi)/7...

If in ` A B C ,A=pi/7,B=(2pi)/7,C=(4pi)/7` then `a^2+b^2+c^2` must be `R^2` (b) `3R^2` (c) `4R^2` (d) `7R^2`

Text Solution

Verified by Experts

The correct Answer is:
7
Promotional Banner

Topper's Solved these Questions

  • PROPERTIES AND SOLUTION OF TRIANGLES

    ARIHANT MATHS|Exercise Exercise (Subjective Type Questions)|21 Videos

  • PROPERTIES AND SOLUTION OF TRIANGLES

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|21 Videos

  • PROPERTIES AND SOLUTION OF TRIANGLES

    ARIHANT MATHS|Exercise Exercise (Passage Based Questions)|25 Videos

  • PRODUCT OF VECTORS

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|52 Videos

  • SEQUENCES AND SERIES

    ARIHANT MATHS|Exercise Exercise (Questions Asked In Previous 13 Years Exam)|38 Videos

Similar Questions

Explore conceptually related problems

If in hat harr ABC,A=(pi)/(7),B=(2 pi)/(7),C=(4 pi)/(7) then a^(2)+b^(2)+c^(2) must be R^(2)( b) 3R^(2)(c)4R^(2)(d)7R^(2)

In trgABC , a=7, b=2, B= pi /4 then, c= ?

(-4/7 a^2 b)xx(-2/3 b^2c)xx(-7/6 c^2a)

If ' O ' is the circum centre of the A B C and R_1,\ R_2,\ R_3 are the radii of the circumcircle of triangle O B C ,\ O C A\ a n d\ O A B respectively then a/(R_1)+b/(R_2)+c/(R_3) has the value equal to (a b c)/(2R^3) (b) (R^3)/(a b c) (c) (4)/(R^2) (d) (a b c)/(R^3)

In triangle ABC, if r_(1)=2r_(2)=3r_(2), then a:b is equal to (5)/(4) (b) (4)/(5)(c)(7)/(4)(d)(4)/(7)

In !ABC,angleA=pi/2b=4,c=3 ,then the value of R/r is equal to

With usual notations,in triangle ABC,a cos(B-C)+b cos(C-A)+c cos(A-B) is equal to (a)(abc)/(R^(2)) (b) (abc)/(4R^(2)) (c) (4abc)/(R^(2)) (d) (abc)/(2R^(2))

In a triangle ABC,a=4,b=3,/_A=60^(@) then c is root of the equation c^(2)-3c-7=0 (b) c^(2)+3c+7=0(c)c^(2)-3c+7=0(d)c^(2)+3c-7=0

ARIHANT MATHS-PROPERTIES AND SOLUTION OF TRIANGLES -Exercise (Single Integer Answer Type Questions)
  1. If in Delta ABC, / C=pi/8, a= sqrt2 and b= sqrt(2+sqrt2) then find the...

    Text Solution

    |

  2. If in A B C ,A=pi/7,B=(2pi)/7,C=(4pi)/7 then a^2+b^2+c^2 must be R^2 ...

    Text Solution

    |

  3. If A, B, C the angles of an acute angled Delta ABCand D=|{:((tan B+ ta...

    Text Solution

    |

  4. In a DeltaABCP and Q are the mid-point or AB and AC, respectively. If ...

    Text Solution

    |

  5. With usual notation in Delta ABC, the numerical value of ((a+b+c)/(r...

    Text Solution

    |

  6. D is midpoint of BC in Delta ABC such that AD and AC are perpendicular...

    Text Solution

    |

  7. In a triangle ABC, medians AD and CE are drawn. If AD=5, angle DAC=pi/...

    Text Solution

    |

  8. In Delta ABC, (r )/(r(1))=1/2, then the valur of 16 (sum tan ((A)/(2))...

    Text Solution

    |

  9. In a DeltaABC, the maximum value of 120((sum a cos ^(2)((A)/(2)))/(a+...

    Text Solution

    |

  10. The sides of a triangle arr three consective natural numbers and its l...

    Text Solution

    |

  11. In DeltaABC, angle C = 2 angle A, and AC = 2BC, then the value of (a^(...

    Text Solution

    |

  12. If a, b and A are given in a triangle and c(1), c(2) are possible valu...

    Text Solution

    |

  13. In triangle ABC, a=5, b=4, c=3. G is the centroid of trianggle. If R(...

    Text Solution

    |

  14. A triangle A B C is inscribed in a circle with centre at O , The lines...

    Text Solution

    |

  15. In Delta ABC, a ge b ge c and if (a^(3) +b^(2)+ c^(2))/(sin ^(3) A sin...

    Text Solution

    |

  16. In a cyclic quadrilateral PQRS, PQ= 2 units, QR= 5 units, RS=3 units ...

    Text Solution

    |