How do you solve #2cos^2 theta + cos theta -1 = 0#?
1 Answer
Sep 15, 2016
Explanation:
Solve the quadratic equation for cos t.
Since a - b + c = 0, use shortcut. The 2 real roots are:
cos t = -1 and
Use trig table of special arcs and unit circle -->
a. cos t = -1 -->
General answers:
b.
arc
General answers: