I would convert to degrees first seems to make it easier.
×
= -468
by adding 360 twice we get the coterminal angle 252
252 is in the 3rd quadrant so 180 is the closest angle on the x-axis
ref angle = 252 - 180 = 72
If necessary convert back to radians...
= -468
by adding 360 twice we get the coterminal angle 252
252 is in the 3rd quadrant so 180 is the closest angle on the x-axis
ref angle = 252 - 180 = 72
If necessary convert back to radians...