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Matrices

Matrices

Scalar 	1 number						
Vector	1 col or one row array						
Matrix	2 dimensions cols and rows						
Tensor	multiple dimensions row,col,axis						
						
Matrix	Not commutative A*B <> B*A						
        Associative A(B*C) = (A*B)C						
        Distributive A(B+C) = A*B + A*C						
						
Identity    1    0    0				
            0    1    0				
            0    0    etc				
						
Inverse	A*Inverse =  Identity (calculate by simultaneous equations or Gaussian elimination)				

A2 + B2 = C2 Proof

( b ) a
__ __ __
a | | { b
b { | | {
{ |__ __ __| a
a ( b )

Draw lines inside square to make 4 triangles of dimension a, b and c.