Can someone help me prove two theorems? I know they both are true, but can't come up with proofs.(adsbygoogle = window.adsbygoogle || []).push({});

1) Prove that a 3x3 matrix A is orientation preserving iff det(A)>0.

2) Prove that for A, B (both 3x3 matrices) that det(AB)=detA*detB. (A, B may or may not be invertible).

THANK YOU!!!!

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# Orientation preserving and determinants

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