document.write( "Question 1182856: Determine which of the following are subspaces of M22.\r
\n" ); document.write( "\n" ); document.write( "(i) All matrices a b where a+b+c+d=0
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\n" ); document.write( "\n" ); document.write( "(ii) All 2×2 matrices A such that det (A)=0\r
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Algebra.Com's Answer #812953 by ikleyn(53763) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "If you know the definition of a sub-space (which I assume), then you easily will come to the following answers:\r\n" );
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document.write( "(i)    YES\r\n" );
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document.write( "(ii)   NO  (because det(A) = 0 and det(B) = 0 do not imply det(A+B) = 0)\r\n" );
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document.write( "(iii)  YES\r\n" );
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