" 4."tan20^(@)+tan40^(@)+sqrt(3)tan20^(@)tan40^(@)=

tan20^(@)-tan80^(@)+sqrt(3)tan20^(@)tan80^(@)=

Find tan 20^(@) + tan40^(@) + sqrt(3)tan20^(@)tan40^(@) .

Assertion (A) tan20^(@)+tan40^(@)+sqrt(3)tan20^(@)tan40^(@)=sqrt(3)Rason(R):If tan(A+B)=k, then tan A+tan B+k tan A tan B=0

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:

tan40^(@)+tan80^(@)-sqrt(3)tan40^(@)tan80^(@)=

The value of tan20^(@)+tan40^(@)+sqrt(3)tan20^(@)tan40^(@) is

A=(cos9^(@)-sin9^(@))/(cos9^(@)+sin9^(@)),B=(cos21^(@)+sin21^(@))/(cos21^(@)-sin21^(@)) and C=tan20^(@)+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

tan20^(@)-tan80^(@)+sqrt(3)=