The value of the following is : $$\frac{{{{\left( {\tan {{20}^ \circ }} \right)}^2}}}{{{{\left( {{\text{cosec 7}}{0^ \circ }} \right)}^2}}}$$   $$ + $$ $$\frac{{{{\left( {\cot {{20}^ \circ }} \right)}^2}}}{{{{\left( {{\text{sec 7}}{0^ \circ }} \right)}^2}}}$$   $$ + $$ $$2\tan {15^ \circ }$$ . $$\tan {45^ \circ }$$ . $$\tan {75^ \circ }$$

Solution(By Examveda Team)

$$\frac{{{{\left( {\tan {{20}^ \circ }} \right)}^2}}}{{{{\left( {{\text{cosec 7}}{0^ \circ }} \right)}^2}}}$$   $$ + $$ $$\frac{{{{\left( {\cot {{20}^ \circ }} \right)}^2}}}{{{{\left( {{\text{sec 7}}{0^ \circ }} \right)}^2}}}$$   $$ + $$ $$2\tan {15^ \circ }$$ . $$\tan {45^ \circ }$$ . $$\tan {75^ \circ }$$
$$\eqalign{ & \Rightarrow \frac{{{{\left( {\tan {{20}^ \circ }} \right)}^2}}}{{{\text{se}}{{\text{c}}^2}{{20}^ \circ }}} + \frac{{{{\left( {\cot {{20}^ \circ }} \right)}^2}}}{{{\text{cose}}{{\text{c}}^2}{{20}^ \circ }}} + 2\tan {15^ \circ }.\tan {75^ \circ } \cr & \left[ {{\text{tan 1}}{5^ \circ }{\text{.tan 7}}{5^ \circ } = {\text{1}}{\text{. If, A}} + {\text{B}} = {{90}^ \circ }} \right] \cr & \Rightarrow \left( {{{\sin }^2}{{20}^ \circ } + {\text{co}}{{\text{s}}^2}{{20}^ \circ }} \right) + 2 \cr & \Rightarrow 1 + 2 \cr & \Rightarrow 3 \cr} $$