Question

Evalute the expressions:

1). sin(π/3)+cos(π/3)

2). (cos 45°)^2-(sin 45°)^2

Answer 1

draw a 30-60-90 triangle
cos60=1/2 sin60=1/2 *sqrt3

draw a 45-45-90 triangle
cos45=1/sqrt2
sin45=1/sqrt2

I hope that helps