JAMIA MILLIA ISLAMIA Jamia Millia Islamia Solved Paper-2008

  • question_answer
        If the angles of a triangle are in the ratio\[3:4:5,\]then the sides are in the ratio ,

    A)  \[2:\sqrt{6}:\sqrt{3}+1\]             

    B)  \[\sqrt{2}:\sqrt{6}:\sqrt{3}+1\]

    C)  \[2:\sqrt{3}:\sqrt{3}+1\]             

    D)  \[3:4:5\]

    Correct Answer: A

    Solution :

                    Let the angles of a triangle are 39, 49, 59. We know, \[\angle A+\angle B+\angle C=180{}^\circ \] \[\Rightarrow \]               \[3\theta +4\theta +5\theta =180{}^\circ \] \[\Rightarrow \]               \[12\theta =180{}^\circ \] \[\Rightarrow \]                               \[\theta =15{}^\circ \] \[\therefore \]Angles are\[45{}^\circ ,\text{ }60{}^\circ ,\text{ }75{}^\circ \] Now,     \[sin\text{ }A=sin\text{ }45{}^\circ =\frac{1}{\sqrt{2}}\] \[sin\,B=sin\,60{}^\circ =\frac{\sqrt{3}}{2}\]                 \[sin\,C=sin\,75{}^\circ =\frac{\sqrt{3}+1}{2\sqrt{2}}\] \[\therefore \]  \[a:b:c=sin\text{ }A:sin\text{ }B:sin\text{ }C\]                 \[=\frac{1}{\sqrt{2}}:\frac{\sqrt{3}}{2}:\frac{\sqrt{3}+1}{2\sqrt{2}}\]


You need to login to perform this action.
You will be redirected in 3 sec spinner