1. A is an orthogonal matrix 
a.1 
2. A is an invertible matrix 
b.3 
3. P(A) where 
c. AA^{T} where A is a square matrix 
4. P(A) where 
d. AB = BA = I for some B 
5. Symmetric matrix system of equations AX = B where 
e. AA^{T} = A^{T}A = I 
6. a ≠ 3, b any number 
f. No solution 
7. a = 3, b ≠ 10 
g. Finitely many solutions 
8. a = 3, b = 10 
h. Unique solution 

i. Infinite ... 
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