A triangle has sides A, B, and C. Sides A and B are of lengths 1 and 4, respectively, and the angle between A and B is pi/6. What is the length of side C?

Jun 24, 2018

Length of side C = 3

Explanation:

$a = 1 , b = 4 , \hat{C} = \frac{\pi}{6}$

As per Law of cosines,

c = sqrt(a^2 + b^2 - 2 ab cos C

c = sqrt(1^2 + 4^2 - (2*2*4*cos (pi/6))

$c = \sqrt{1 + 16 - 8} = 3$