document.write( "Question 29839: I have to solve this proof but dont understand it all.
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document.write( "Here it is: Let v and w be independent column vectors in R^3, and let A be an invertible 3X3 matrix.Prove that the vectors Av and Aw are independent. \n" );
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Algebra.Com's Answer #16588 by khwang(438)![]() ![]() ![]() You can put this solution on YOUR website! You have to know a linear transformation T:V-->V is invertible(one-to-one) \n" ); document.write( " <--> Ker(T)(null space of T) = {0} \n" ); document.write( " Let v and w be independent column vectors in R^3, and let A be \n" ); document.write( " an invertible 3X3 matrix.\r \n" ); document.write( "\n" ); document.write( "Prove that the vectors Av and Aw are independent. \n" ); document.write( " Proof: A: R^3-->R^3 invertible <--> N(A) = {0} <--> rank A = 3. \n" ); document.write( " a Av + b Aw = 0 for two reals a, b \n" ); document.write( " --> A(av+bw) = 0 \n" ); document.write( " --> av + bw belongs to N(A)= {0} \n" ); document.write( " --> av+vw = 0 \n" ); document.write( " --> a=b = 0 (since v, w are lindep.) \n" ); document.write( " Hence, Av & Aw are l.indep.\r \n" ); document.write( "\n" ); document.write( " This fact is true for any number of indep vectors. \n" ); document.write( " Also, it seems you have to work hard.\r \n" ); document.write( "\n" ); document.write( " Kenny \n" ); document.write( " |