Question

Find the exact value of sin (o)

Answer 1

The best way to think about this value is to picture the graph of the "normal" sin wave.  One period starts at (0, 0), goes up to a y value of 1 at an x value of $\frac{ \pi }{2}$,  goes back down to a y value of 0 at x = $\pi$, goes down to a y value of -1 at x = $\frac{3 \pi }{2}$ and ends up completing one period at a y value of 0 and an x value of $2 \pi$.  We can see from that what the sin ratios are at each one of those x values.  When x = 0, y = 0, so the sin of 0 is 0.  Check your calculator to see that this is true, but understanding the graph tells you WHY it is true.