If cosθ + secθ = $$\sqrt 3 ,$$ then the value of (cos3θ + sec3θ) is?
A. $$\frac{1}{{\sqrt 2 }}$$
B. 1
C. 0
D. $$\sqrt 2 $$
Answer: Option C
Solution(By Examveda Team)
$$\eqalign{ & {\text{cos}}\theta + \sec \theta = \sqrt 3 \cr & {\text{Cubing both sides}} \cr & {\text{co}}{{\text{s}}^3}\theta + {\sec ^3}\theta + 3{\text{cos}}\theta \sec \theta \left( {{\text{cos}}\theta + \sec \theta } \right) = 3\sqrt 3 \cr & {\text{co}}{{\text{s}}^3}\theta + {\sec ^3}\theta + 3\sqrt 3 = 3\sqrt 3 \cr & {\text{co}}{{\text{s}}^3}\theta + {\sec ^3}\theta = 0 \cr} $$Related Questions on Trigonometry
A. x = -y
B. x > y
C. x = y
D. x < y
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