**Unformatted text preview: **AB is nonsingu-lar. / When you become good enough at writing proofs, you can use the following way, though I do not recommend you to do it now . Proof. AB is nonsingular. ⇐⇒ det( AB ) 6 = 0. (By Theorem 2.2.2) ⇐⇒ det( A )det( B ) 6 = 0. (By Theorem 2.2.3) ⇐⇒ Both det( A ) 6 = 0 and det( B ) 6 = 0. ⇐⇒ Both A and B are are nonsingular. (By Theorem 2.2.2) / 1...

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- Spring '08
- samiabdul
- Linear Algebra, Algebra, Following, Det, Mathematical proof