Temperament addition: Difference between revisions

Cmloegcmluin (talk | contribs)
make corrections re: linear (in)dependence vs. collinearity, as well as vectors vs. basis vectors (thanks for the feedback, Sintel!)
Cmloegcmluin (talk | contribs)
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If A and B are mappings from Z^n to Z^m, with n > m, A, B full rank (i'll use A and B as their rowspace equivalently):
If A and B are mappings from Z^n to Z^m, with n > m, A, B full rank (i'll use A and B as their rowspace equivalently):
dim(A + B) - m = dim(ker(A) + ker(B)) - (n-m)
dim(A + B) - m = dim(ker(A) + ker(B)) - (n-m)
>> dim(A)+dim(B)=dim(A+B)+dim(A∩B) => dim(A + B) = dim(A) + dim(B) - dim(A∩B)
>> dim(A)+dim(B)=dim(A+B)+dim(A∩B) => dim(A + B) = dim(A) + dim(B) - dim(A∩B)
dim(A) + dim(B) - dim(A∩B) - m = dim(ker(A) + ker(B)) - (n-m)
dim(A) + dim(B) - dim(A∩B) - m = dim(ker(A) + ker(B)) - (n-m)
>> by duality of kernel, dim(ker(A) + ker(B))  = dim(ker(A ∩ B))  
 
>> by duality of kernel, dim(ker(A) + ker(B))  = dim(ker(A ∩ B))
 
dim(A) + dim(B) - dim(A∩B) - m = dim(ker(A ∩ B))  - (n-m)
dim(A) + dim(B) - dim(A∩B) - m = dim(ker(A ∩ B))  - (n-m)
>> rank nullity: dim(ker(A ∩ B)) + dim(A ∩ B) = n
>> rank nullity: dim(ker(A ∩ B)) + dim(A ∩ B) = n
dim(A) + dim(B) - dim(A∩B) - m = n -  dim(A ∩ B)  - (n-m)
dim(A) + dim(B) - dim(A∩B) - m = n -  dim(A ∩ B)  - (n-m)
m + m - dim(A∩B) - m = n -  dim(A ∩ B)  - (n-m)
m + m - dim(A∩B) - m = n -  dim(A ∩ B)  - (n-m)
m + m - m = n - n + m
m + m - m = n - n + m
m = m
m = m