Problem : Use α = 30o and β = 45o to find the sine, cosine, and tangent of 75o.

sin(75o) = sin(30o +45o) = sin(30o)cos(45o) + cos(30o)sin(45o) 0.9659. cos(75o) = cos(30o +45o) = cos(30o)cos(45o) - sin(30o)sin(45o) 0.2588. tan(75o) = tan(30o +45o) = 3.732.

Problem : Use α = 135o and β = 30o to find the sine, cosine, and tangent of 105o.

sin(105o) = sin(135o -30o) = sin(135o)cos(30o) - cos(135o)sin(30o) 0.9659. cos(105o) = cos(135o -30o) = cos(135o)cos(30o) + sin(135o)sin(30o) - 0.2588. tan(105o) = tan(135o -30o) = - 3.732.

Problem : Express the following as a function of a single angle: sin(20o)sin(30o) + cos(20o)cos(30o).

cos(- 10o)

Problem : Express the following as a function of a single angle: .

tan(72o)

Problem : Express the following as a function of a single angle: sin(340o)cos(120o) + cos(340o)sin(120o).

sin(460o) = sin(100o).