Recent content by a.merchant

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    Matrix Subspaces: Does Set W = {X: AX=2X} Form a Subspace of M(2,1)?

    So i could just state that: 0 E W as the zero matrix times any 2x2 matrix will be all 0's, so it is equal to 2x the zero matrix (not in so many words, I am just not sure how to write matrices in this forum) for the zero part?
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    Matrix Subspaces: Does Set W = {X: AX=2X} Form a Subspace of M(2,1)?

    Homework Statement Let A be a fixed 2x2 matrix. Assuming that the set: W={X:AX=2X} has infinitly many solutions, determine whether it is a subspace of M(2,1) Homework Equations To determine whether a set is a subspace i need to prove that there is a zero vector, that it is closed under...
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    Proving that the product rule for differentiating products applies to vectors

    If r and s are vectors that depend on time, prove that the product rule for differentiating products applies to r.s, that is that: d/dt (r.s) = r. ds/dt + dr/dt .s -- I'm not entirely sure how I'm supposed to go about proving this, can anyone point me in the right direction, please...