Precal
posted by Hannah on .
1) Find two values of Q that satisfy the equation. Give your answer is degrees and radians. Do not use a calculator.
a) sec Q = 2
pi/3 and 60 degrees
Is this correct?
b) sec Q = 2
This one I do not know how to find.

I will do the second one.
The first thing I do is to change the expression into one of the 3 basic trig ratios.
sec Q = 2 > cos Q = 1/2
I then find the "angle in standard position", which is the angle it the first quadrant.
You have to know your 306090 and your 454590 ratio of sides.
we know cos 60º = 1/2
From the CAST rule, I know that the cosine is negative in quadrants II and III
so Q = 180  60 = 120º (quadrant II)
or
Q = 180 + 60 = 240º (qudrant III)
of course in radians that would be 2pi/3 and 4pi/3
Now redo the first one, you are missing an angle. (where else is the cosine positive ?)