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njiokm
M2x3 forms a vector space, Does the set N2x3, which consists of all 2x3 matrices with nonnegative entries form a subspace of M2x3? Justify your answer.
Nope, because when when 2*3 matrix consisting of non negative entries is multiplied by a negative integer, the resultant 2*3 matrix will not be under N2*3.