[tan27^(@)tan32^(@)+tan32^(@)],[tan31^(@)+tan31^(@)tan27^(@)=]

tan25^(@).tan31^(@)+tan31^(@).tan34^(@)+tan34^(@)*tan25^(@)=

tan9^(@)-tan27^(@)-tan63^(@)+tan81^(@)=?

tan9^(@)-tan27^(@)-tan63^(@)+tan81^(@)=

Prove that (2)/(3)csc^(2)58^(@)-(2)/(3)cot58^(@)tan32^(@)-(5)/(3)tan13^(@)tan37^(@)tan45^(@)tan53^(@)tan77^(@)

Prove that: (a) tan 20^(@)tan40^(@)tan60^(@)tan 80^(@)=3 (b) tan9^(@)-tan27^(@)-tan63^(@)+tan81^(@)=4

The value of the expression tan13^(@)tan27^(@)+tan27^(@)tan50^(@)+tan50^(@)tan13^(@) is equal to

tan9^(0)-tan27^(0)-tan63^(@)+tan81^(@)

(1+tan18^(@)) (1+tan27^(@))=