SOLUTION: Sin(210) can you show me how do arrive at the answer?

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Question 1122825: Sin(210) can you show me how do arrive at the answer?
Found 2 solutions by josgarithmetic, josmiceli:
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
Quadrant 3; between 180 degrees and 270 degrees. The sine function is negative there.
210-180=30;

Compare as reference to 30 degree angle. Sine? The negative?


-1%2F2

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+sin%28+210+%29+=+sin%28+180+%2B+30+%29+
Rotating the unit vector from 0 degrees in the
Positive direction to +210+ degrees puts it
+30+ degrees past +180+
which is in the 3rd quadrant.
In the 3rd quadrant, the sin is negative, so
+sin%28+210+%29+=+-sin%28+30+%29+
+sin%28+210+%29+=+-1%2F2+