1.

\({\left( {1 + {\rm{tanA}}} \right)^2} + {\left( {1{\rm{\;}} - {\rm{\;tanA}}} \right)^2}\) is equal to1). 2cosec2A2). cosec2A3). sec2A4). 2 sec2A

Answer»

$(\RIGHTARROW {\rm{\;}}{\LEFT( {1 + {\rm{tanA}}} \right)^2} + {\left( {1{\rm{\;}} - {\rm{\;tanA}}} \right)^2})$

$(\Rightarrow 1 + 2{\rm{tanA}} + {\tan ^2}{\rm{A}} + 1{\rm{\;}} - {\rm{\;}}2{\rm{tanA}} + {\tan ^2}{\rm{A}} = 2 + 2{\tan ^2}{\rm{A\;}})$

$(= 2\left( {1 + {\rm{TA}}{{\rm{N}}^2}{\rm{\;A}}} \right) = {\rm{\;}}2{\sec ^2}{\rm{A}})$



Discussion

No Comment Found