`A=(cos 9^@-sin 9^@)/(cos 9^@ + sin 9^@), B=(cos 21^@ +sin 21^@)/(cos 21^@ -sin 21^@) and C = tan 20^@ + tan 40^@ + sqrt3 tan 20^@ tan 40^@` then descending order is

A=(cos9^(@)-sin9^(@))/(cos9^(@)+sin9^(@)),B=(cos21^(@)+sin21^(@))/(cos21^(@)-sin21^(@)) and C=tan20^(@)+tan40^(@)+sqrt(3)tan20^(@)tan40^(@) then descending order is

A =(cos 9^(@) - sin 9^(@))/(cos 9^(@) + sin 9^(@)) , B = (cos 21^(@) + sin 21^(@))/(cos21^(@) -sin21^(@)) and C= tan 20^(@) + tan40^(@) + sqrt(3)tan20^(@) tan40^(@) then descending order is:

A=(cos9^(@)-sin9^(@))/(cos9^(@)+sin 9^(@)), B=(cos21^(@)+sin21^(@))/(cos21^(@)-sin21^(@)) and C=tan 20^(@)+tan 40^(@)+sqrt(3)tan20^(@)tan40^(@) then descending order is

sin 21^(@) cos 9^(@) - cos 84^(@) cos 6^(@)=

Prove that (cos9^@+sin9^@)/(cos9^@-sin9^@)=tan54^@

(cos9^(@)+sin9^(@))/(cos9^(@)-sin9^(@))=tan54^(@)

(cos21^(@) -sin21^(@))/(cos21^(@) + sin21^(@)) A) tan21^(@) B) cot66^(@) C) tan42^(@) D) cot42^(@)

Prove that (cos 9^(@)+ sin 9^(@))/(cos 9^(@) -sin 9^(@)) = tan 54^(@)

Prove that (cos 9^(@)+ sin 9^(@))/(cos 9^(@) -sin 9^(@)) = tan 54^(@)