#3**+3 **

41. Here is the solution:

Imagine the unit circle:

We know that 300 degrees is in the fourth quadrant, where cosine is positive.

300 degrees has a reference angle of 60 degrees, since it is 60 degrees away from the x-axis

Since \(\cos{60º}=\frac12, \cos{300º}=\frac12\)

I hope this helped,

Gavin

GYanggg
May 17, 2018

#4**+3 **

42. Assuming s is the major arc, here is the solution:

π here is 180 degrees, so 5π/3 is also 5 * 180 / 3 = 300

That angle is 300 degrees.

The circumference is 2r * π, where r is the radius and π is 3.1415...

The circumference is 18π.

Since the major arc is 300/360 or 5/6 of the circumference, it is

5/6 * 18π = 15π long.

This in decimal is 15 • 3.141...=47.124...

A.

I hope this helped,

Gavin

GYanggg
May 17, 2018