Question

Simplify cos(-1/3+-1/4)

Answer 1

Cod (-0.3-0.25)=
cos (-0.55)=0.45.

Answer 2

Hello :
cos(-π/3 -π/4)  =  cos(-  (π/3 +π/4)  ) = cos  (π/3 +π/4)  
                       = cos(π/3) cos(π/4) - sin(π/3) sin(π/4) 
                       = (1/2)(√(2)/2) - (√(3)/2)(√(2)/2)
                       =(√(2)-√(6)/)/4