question_answer

If a sec \[\alpha -c\]tan \[\alpha =d\]and b sec \[\alpha +d\]tan\[\alpha =c,\] then

A)  \[ab=cd\]     

B)  \[{{a}^{2}}+{{d}^{2}}={{c}^{2}}+{{b}^{2}}\]

C)  \[{{a}^{2}}+{{c}^{2}}={{b}^{2}}+{{d}^{2}}\]

D)     \[{{a}^{2}}+{{b}^{2}}={{c}^{2}}+{{d}^{2}}\]