Find the value of \(\theta\) in the diagram
A.
60o
B.
100o
C.
120o
D.
30o
Correct answer is C
Using cosine formula (t\(\sqrt{3}\))2 = t2 + t2 - 2t2 cos\(\theta\)
3t2 = 2t2 - 2t2 cos\(\theta\) = 2t2(1 - cos\(\theta\))
1 - cos\(\theta\) = \(\frac{3t^2}{2t^2}\) = \(\frac{3}{2}\)
cos = 1 - \(\frac{3}{2} = -\frac{1}{2}\)
\(\theta\) = cos-1(-\(\frac{1}{2}\)) = 120o and 240o
N.B 0 \(\geq\) \(\theta\) 360