Question

Find all degree solutions. (Enter your answers in the form a + bk, where a is in [0, 180), b is the smallest possible positive number, and k represents any integer. Enter solutions from smallest to largest a - value.)
2\cos^{2} ({6}\theta) + 3\cos ({6}\theta)+1=0

Answer 1

\[2\cos^{2} ({6}\theta) + 3\cos ({6}\theta)+1=0 \]

Answer 2

This is a quadratic equation in cos^2. Factor and solve for theta.

Answer 3

\[
2\cos^{2} ({6}\theta) + 3\cos ({6}\theta)+1=0 \\
2\cos^{2} ({6}\theta) + 2\cos ({6}\theta) + \cos ({6}\theta) +1=0 \\
2\cos(6\theta)*(\cos(6\theta)+1) + 1(\cos(6\theta)+1) = 0 \\
(2\cos(6\theta)+1)*(\cos(6\theta)+1) = 0 \\
\cos(6\theta) = -\frac 12~~~\text{ or }~~~\cos(6\theta) = -1
\]Solve for theta.

Answer 4

wow its u again!

Answer 5

ur going to kill me. i put the wrong one up. i actually already resolved this one

Answer 6

np. close the question.