Maths-
General
Easy

Question

If the sides of a triangle are in the ratio x colon y colon square root of x squared plus x y plus y squared end root then greatest angle is

  1. 90 to the power of ring operator
  2. 120 to the power of ring operator
  3. cos to the power of negative 1 end exponent invisible function application open parentheses fraction numerator x plus y over denominator x minus y end fraction close parentheses
  4. 60 to the power of ring operator

hintHint:

In this question, we have to find the angle of the greatest angle. As c is the greatest side so angle C is the greatest angle. As we know the sides ratio, so using the cosine formula we will find the angle of the greatest side.

The correct answer is: 120 to the power of ring operator


    As the ratio of the sides is x colon y colon square root of x squared plus x y plus y squared end root
    a= x, b=y, c =square root of x squared plus x y plus y squared end root
    c is the largest side, so, C is the largest angle.
    cos space C space equals open parentheses fraction numerator a squared plus b squared minus c squared over denominator 2 a b end fraction close parentheses
space space space space space space space space space space space equals open parentheses fraction numerator x squared plus y squared minus open parentheses x squared plus x y plus y squared close parentheses over denominator 2 x y end fraction close parentheses
space space space space space space space space space space space equals open parentheses fraction numerator x squared plus y squared minus x squared minus y squared minus x y over denominator 2 x y end fraction close parentheses
space space space space space space space space space space space equals fraction numerator negative x y over denominator 2 x y end fraction
space space space space space space space space space space equals fraction numerator negative 1 over denominator 2 end fraction
rightwards double arrow cos space C equals cos space 120 degree
rightwards double arrow C equals 120 degree
    So, the angle of the greatest angle is 120degree.

    card img

    With Turito Academy.

    card img

    With Turito Foundation.

    card img

    Get an Expert Advice From Turito.

    Turito Academy

    card img

    With Turito Academy.

    Test Prep

    card img

    With Turito Foundation.