[tex] \frac{\pi}{6} [/tex]
When you are asked what is the sin of π/6, or 30 degrees, you would look at the special triangle (30-60-90) to see that sin, or opposite over hypotenuse, of π/6 is 1/2. Arcsin, or csc, will present you with the ratio, 1/2, and ask for the angle. It's essentially working the question backwards.
