i wonder how can i get the exact sinus of the angle between two vectors. one solution is thru the vector product.since(adsbygoogle = window.adsbygoogle || []).push({});

|XxY|=|X||Y|sin(<X,Y>) then

sin(<X,Y>)=|XxY|/(|X||Y|)

unfortunately i don't know when |XxY|>0 and when |XxY|<0 cause

|XxY|=(+/-)sqrt(sqr(XxY(1))+sqr(XxY(2))+sqr(XxY(3))).

how can i be sure when to use + when to use -?

or maybe there is another way to do it?

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# Sinus of the angle between two vectors

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