Basically, we have to prove that A X B is equal to ABsinθ(adsbygoogle = window.adsbygoogle || []).push({});

Now a crucial step towards the proof is proving that

(AXB).(AXB) is equal to (AB)^{2}- (A.B)^{2}

After that it is fairly simple. But unfortunately, I can not prove the identity. I've tried expanding it into components but things are becoming messy. Any idea on how to prove this identity (namely : (AXB).(AXB)= (AB)^{2}- (A.B)^{2}) ?

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# Homework Help: Reconcile Geometric Form of Cross Product with Algebric Form

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