Trigonometry

Identities for the sum and difference of two angles

Keywords: Identities for the sum and difference of two angles

s i n ( α + β ) = s i n α   c o s β + c o s α   s i n β

s i n ( α β ) = s i n α   c o s β c o s α   s i n β

c o s ( α + β ) = c o s α   c o s β s i n α   s i n β

c o s ( α β ) = c o s α   c o s β + s i n α   s i n β

 

t g ( α + β ) = t g α + t g β 1 t g α   t g β

t g ( α β ) = t g α t g β 1 + t g α   t g β