A painter can paint 1/3 of a wall
in 2/3 of an hour. How many
walls can he paint in 6 hours?

6 walls

Step-by-step explanation:

First find how much of the wall he can paint in 1 hour.

Then multiply by 6 to get how many walls he can paint in 6 hours

You are given the function of  identity of cos(6x) = 2cos^2(3x)-1. A sine and cosine function is one of the basic functions encountered in Trigonometry. Sine is equal to the opposite side over hypotenuse whereas the cosine function is equal to the adjacent side over the hypotenuse.