Change
to degrees:
We subtract 360° enough times to get a
a positive coterminal angle less than 360°:
660°-360° = 300° (it was only necessary to
subtract 360° one time.)
That is in QIV, So to get the reference
angle, we subtract from 360° and get
360°-300° = 60°.
The secant, which is the reciprocal
of the cosine, and the cosine is +
in QIV, so








Edwin