Re: Linear algebra, matrices, and you
in case noone has answered yet:
1) True: x.x is the length of the vector squared.
2) False: set all entries in C =0, A and B can then be any two matricies.
3)True: A=AI=ACB=IB=B
4) True: I assume by square you mean no. of rows = no. of columns, if so this is really obvious
Bonus:
(Ax) . (Ay) = (Ax)T (Ay) = xT AT A y = xT I y = xT y= x . y
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