Trigonometric Equations Question 253

Question: The smallest angle of the triangle whose sides are $ 6+\sqrt{12},\sqrt{48},\sqrt{24} $ is

[EAMCET 1985]

Options:

A) $ \frac{\pi }{3} $

B) $ \frac{\pi }{4} $

C) $ \frac{\pi }{6} $

D) None of these

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Answer:

Correct Answer: C

Solution:

  • Let $ A=6+\sqrt{12},b=\sqrt{48},c=\sqrt{24} $ . Clearly, c is the smallest side. Therefore, the smallest angle C is given by $ \cos C=\frac{a^{2}+b^{2}-c^{2}}{2ab}=\frac{\sqrt{3}}{2}\Rightarrow C=\frac{\pi }{6} $ .