For two arbitrary vectors in 3D space, subtending an angle, [tex] \gamma [/tex] , I know the cos relationship, but what's the sin relationship ? I ask because there is an ambiguity by only knowing the cosine form, since vector A can be either above or below vector B.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

cos\gamma = cos\theta_1 cos\theta_2 + sin\theta_1 sin\theta_2 cos( \phi_1 - \phi_2 )

[/tex]

Sorry I ask a stupid question in this forum, but I didn't know what's the correct term I should type in the search engine to search in the internet.

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# Gamma angle

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