Question

I need to write the expression as the sine of an angle Number 8

Answer 1

Answer:

sin (60° - 20)°

sin (40°)

Step-by-step explanation:

Note that:

sin(A - B) = sinAcosB - cosAsinB

The given trigonometric expression is:

sin 60° cos 20° - cos 60° sin 20°

Applying the addition rule of trigonometry written above:

sin 60° cos 20° - cos 60° sin 20° = sin(60° - 20°)

This can also be written as sin (40°)