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?
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...
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
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I'm not entirely sure how I'm supposed to go about proving this, can anyone point me in the right direction, please...