If 0° < A < 90°, then the value of tan2A + cot2A - sec2A cosec2A is?
A. 0
B. 1
C. 2
D. -2
Answer: Option D
Solution(By Examveda Team)
$$\eqalign{ & {\text{ta}}{{\text{n}}^2}{\text{A}} + {\text{co}}{{\text{t}}^2}{\text{A}} - {\sec ^2}{\text{A}}{\text{.cose}}{{\text{c}}^2}{\text{A}} \cr & {\bf{Shortcut\,\, method:}} \cr & {\text{Put A}} = {45^ \circ } \cr & \Rightarrow {\text{ta}}{{\text{n}}^2}{45^ \circ } + {\text{co}}{{\text{t}}^2}{45^ \circ } - {\sec ^2}{45^ \circ }{\text{.cose}}{{\text{c}}^2}{45^ \circ } \cr & \Rightarrow 1 + 1 - {\left( {\sqrt 2 } \right)^2}{\left( {\sqrt 2 } \right)^2} \cr & \Rightarrow - 2 \cr} $$Related Questions on Trigonometry
A. x = -y
B. x > y
C. x = y
D. x < y
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