Evaluate the following expression in terms of trigonometric ratios. $$\frac{{\sec A - \tan A}}{{\sec A + \tan A}}$$
A. 1 + 2tan2A - 2secAtanA
B. 1 + 2sec2A - 2secAtanA
C. 1 + 2sec2A + 2secAtanA
D. 1 + 2tan2A + 2secAtanA
Answer: Option A
Solution(By Examveda Team)
$$\eqalign{ & \frac{{\sec A - \tan A}}{{\sec A + \tan A}} \cr & = \frac{{\sec A - \tan A}}{{\sec A + \tan A}} \times \frac{{\sec A - \tan A}}{{\sec A - \tan A}} \cr & = \frac{{{{\left( {\sec A - \tan A} \right)}^2}}}{{{{\sec }^2}A - {{\tan }^2}A}} \cr & = \frac{{{{\sec }^2}A + {{\tan }^2}A - 2.\sec A.\tan A}}{1} \cr & = 1 + {\tan ^2}A + {\tan ^2}A - 2.\sec A.\tan A \cr & = 1 + 2{\tan ^2}A - 2.\sec A.\tan A \cr} $$Related Questions on Trigonometry
A. x = -y
B. x > y
C. x = y
D. x < y
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