The value of $$\frac{{\sec \theta \left( {1 - \sin \theta } \right)\left( {\sin \theta + \cos \theta } \right)\left( {\sec \theta + \tan \theta } \right)}}{{\sin \theta \left( {1 + \tan \theta } \right) + \cos \theta \left( {1 + \cot \theta } \right)}}$$        is equal to:

Correct Answer: sinθcosθ
$$\eqalign{ & \frac{{\sec \theta \left( {1 - \sin \theta } \right)\left( {\sin \theta + \cos \theta } \right)\left( {\sec \theta + \tan \theta } \right)}}{{\sin \theta \left( {1 + \tan \theta } \right) + \cos \theta \left( {1 + \cot \theta } \right)}} \cr & = \frac{{\left( {\sec \theta - \tan \theta } \right)\left( {\sin \theta + \cos \theta } \right)\left( {\sec \theta + \tan \theta } \right)}}{{\sin \theta \left( {1 + \tan \theta } \right) + \cos \theta \left( {\frac{{1 + \tan \theta }}{{\tan \theta }}} \right)}} \cr & = \frac{{\left( {{{\sec }^2}\theta - {{\tan }^2}\theta } \right)\left( {\sin \theta + \cos \theta } \right)}}{{\left( {1 + \tan \theta } \right)\left( {\sin \theta + \frac{{{{\cos }^2}\theta }}{{\sin \theta }}} \right)}} \cr & = \frac{{1\left( {\sin \theta + \cos \theta } \right)}}{{\left( {1 + \tan \theta } \right)\left( {\frac{1}{{\sin \theta }}} \right)}} \cr & = \frac{{\left( {\sin \theta + \cos \theta } \right)}}{{\left( {\cos \theta + \sin \theta } \right)}}\sin \theta .\cos \theta \cr & = \sin \theta .\cos \theta \cr} $$