Express the following as a function of a single angle. cos(60) cos(-20) - sin(60) sin(-20)

cos(60) cos(-20) - sin(60) sin(-20) = cos (40)

Step-by-step explanation:

Using the trigonometric identity rule:

Given that:

cos(60) cos(-20) - sin(60) sin(-20)

Let A = 60 and B = -20

then;

Using identity rule:

Therefore, the following as a function of a single angle is cos (40)

the f

last graph i believe

step-by-step explanation:

worked it out i believe