The value of cos 780 using the unit circle is 0.5
Angle in a circle
Given the following angle
To get the equivalent angle, we will need to write the angle to fall between the angles in a circle
cos 780 = cos(780 - 720)
cos 780 = cos 60
cos 780 = 0.5
Hence the value of cos 780 using the unit circle is 0.5
Learn more on unit circle here: https://brainly.com/question/23989157
