Trigonometric Equations Question 228

Question: If the lengths of the sides of a triangle be $ 7,4\sqrt{3} $ and $ \sqrt{13} $ cm, then the smallest angle is

[MNR 1985]

Options:

A) $ 15^{o} $

B) $ 30^{o} $

C) $ 60{}^\circ $

D) $ 45^{o} $

Show Answer

Answer:

Correct Answer: B

Solution:

  • $ \cos \theta =\frac{49+16.3-13}{2.7.4\sqrt{3}}\Rightarrow \theta =30^{o} $ .