Question

If possible find a solution to 2 cos(theta)=-0612.
theta=

Answer 1

if you really mean 0612, then no.

Otherwise, it is always possible to solve

2cos(x) = n
if |n/2| <= 1

Answer 2

That doesnt really help me solve for theta

Answer 3

well, in that case, as you have written it, there is no solution. There is no θ such that

cosθ = -306

If you can figure out what you really meant, learn about the 2nd function for the cos button on your calculator, and the arccos(θ) or cos^-1θ function