Are there any restrictions on x? Usually we solve with the restriction . If that's the case, then we'll need to expand on pickslides' work a bit. If we have the restriction , then it follows that .
For each answer, we need to find coterminal angles to it that is in , so we add 2pi and 4pi to each:
Now take each equation and divide both sides by 3 to solve for x. So we'll get
These are all possible values of x that is in .