This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Triangle with trigonometric proof of the law of cosines.svg Image describing the en Law of cosines koszinuszttel bizonytsa Own Ttbya from PDimage of Rgis Lachaume and second version of Dbenbenn Image Triangle with trigonometric proof of the law of cosines Vectorized version of the above image Law of cosines