tan(x + y) = tan x + tany / 1 - tanx. tany
Ctg x = cos x / sen x
tan2x = 2tanx/1 - tan² x
Tg x = 1/ cotg x
cos 2x = cos ² x - sen ² x
sen(x - y) = senx. cosy - seny . cos x
Cos x = 1/ sec x
cos(x + y) = cosx. cosy - senx .seny
Ctg x =1/ tg x
Tan ² x + 1 = Sec ² x
Csc x = 1/ sen x
Tg x = sen x / cos x
sen(x + y) = senx. cosy + seny . cos x
1 + Cot ² x = Csc ² x
cos(x . y) = cosx. cosy + senx .seny
Sec x = 1/ cos x
tan(x - y) = tan x - tany / 1 + tanx. tany
Sen x = 1/ csc x
Sen ² x + Cos ² x =1
Sen 2x = 2 Senx Cosx
