MHB How to find the answer sin 120.

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I was reading on a forum that $$sin120$$ is equal to$$ sin60$$.

How is this? Shouldn't$$ sin120$$ equal $$sin60 + sin60$$?
 
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tmt said:
I was reading on a forum that $$sin120$$ is equal to$$ sin60$$.

How is this? ...

Good evening,

use the unit circle:
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