6.3 and 6.4 Flashcards
1
Q
When are two matrices equal?
A
When they are the same size and all their elements are the same
2
Q
What is matrix transposition?
A
When you take the rows of a matrix and turn them into the coloumns and vice versa
3
Q
When is a square matrix symmetric?
A
when A = A^T
4
Q
What is the general algorithm of matrix multiplication?
A
Take one element and then multiply the whole coloumn of the other matrix then add them all together and that is just one of the new entries in the new matrix
5
Q
Does AB = BA?
A
No
6
Q
When is a matrix invertible?
A
If there exists an nxn matrix A^-1 satisfying AA^-1 = A^-1A = I
7
Q
If a matrix is not invertible, it is ________
A
singular and det(A) = 0