If $${\text{0}} \leqslant \theta \leqslant {90^ \circ }$$ and $$4{\cos ^2}\theta $$ - $$4\sqrt 3 \cos \theta $$ + 3 = 0 then the value of $$\theta $$ is?
A. 30°
B. 90°
C. 45°
D. 60°
Answer: Option A
Solution(By Examveda Team)
$$\eqalign{ & 4{\cos ^2}\theta - 4\sqrt 3 \cos \theta + 3 = 0 \cr & {\text{Hit and Trial method}} \cr & {\text{Put }}\theta = {30^ \circ }{\text{option A}} \cr & 4{\cos ^2}{30^ \circ } - 4\sqrt 3 \cos {30^ \circ } + 3 = 0 \cr & \Rightarrow 4\left( {\frac{3}{4}} \right) - 4\sqrt 3 \left( {\frac{{\sqrt 3 }}{2}} \right) + 3 = 0 \cr & \Rightarrow 0 = 0 \cr} $$Related Questions on Trigonometry
A. x = -y
B. x > y
C. x = y
D. x < y
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