Question

Q6 Q19.) Write the expression as the​ sine, cosine, or tangent of an angle. Then find the exact value of the expression.

Answer 1

using sin(A+B) = sinAcosB + cosAsinB

sin20cos40 + cos20sin40 = sin(20+40) = sin60degree

= $\frac{ \sqrt{3} }{2}$