precal
posted by stellar on .
Find all solutions of the given equation. (Enter your answers as a commaseparated list. Let k be any integer. Round terms to two decimal places where appropriate.)
2 cos θ − 1 = 0

solve for cosθ the way you would for any other variable.
2cosθ = 1
cos θ = 1/2
ta da. Of course, now you have to now how to find θ, but that's no problem, right?