Nathan's last holiday blog

For this blog, I will review on how to get co-terminal angles in degrees and radians. This was another very easy section.

When trying to find a co-terminal angle, you must add or subtract 360, or if you are in radians, add or subtract 2π.

Find a positive co-terminal angle for 27.
All you have to do is add 27+360=387.

Find a negative co-terminal angle for 18.
All you have to do is subtract 18-360=-342

Find a positive co-terminal angle for 2π/3.
All you have to do is add 2π/3+2π=8π/3

Find a negative co-terminal angle for π/2.
All you have to do is subtract π/2-2π=-3π/2

To find a reference angle you must add or subtract 180 until the angle is between the absolute value of 0 and 90.

Find a reference angle for sin 225 degrees.
Just subtract 225-180= sin45=√2/2

Find a reference angle for cos 180 degrees.
Just subtract 180-180= cos0=1

That's all for this blog.