Question

For this special angle, draw the angle and find the reference angle: t= 2π/3

Answer 1

Answer: C. or the third option.

Another simple way of solving this problem is converting the radian to degrees and then graphing it.

You can convert the radian to degrees by multiplying it by 180/π

[1.] (2π/3) x (180/π) = 360π/2π = 120°

Once you have your degrees, simply graph them on your circle graph. You can use a protractor for this or a online graphing calculator.

[2.] 120° is less than 180°, but greater than 90°, so it will be between those two degrees.

-Your Welcome

Answer 2

C. And the reference angle is pi/3

Explanation:

Let me give you a little quick way to do this. You’re probably trying to memorize the unit circle and figure out what 2pi/3 equals. However, all you need is a bit of math.

Start with the denominator and multiply the numerator by its correct angle

Anything with 3 in it’s denominator, is a multiple of a 60 degree angle. The numerator is 2 so do 60 x 2, which equals 120. Your angle is 120 and will land in the top left quadrant.

Moving on to the reference angle. Think of this as being what you have left on the horizontal axis. The angle took up 120 degrees. Now find the rest. 180 - 120 = 60. Pi/3 equals 60 degrees