Year 1 Chapter 6: Matrices Flashcards
1
Q
How do you get the determinant of the matrix:
( a b )
( c d )
A
ad - bc
2
Q
How can the determinant of M be written as?
A
. . . . . . . . . . . . . . . |a b| , |M| , det M , Δ
|c d|
3
Q
How do you tell if a matrix is singular?
A
If the determinant of the matrix is equal to 0.
4
Q
What is the minor of a 3x3 matrix?
A
The determinant of a 2x2 matrix that remains after the row and column containing the element have been crossed out.
5
Q
What does the inverse of a matrix do?
A
It reverses the matrix so that if you multiply the inverse matrix and the matrix together you get the identity matrix.
6
Q
How do you invert a 2x2 matrix?
A
__𝟷̲__ x ( d -b )
det M (-c a )
7
Q
How do you invert a 3x3 matrix?
A
__𝟷̲__ x C^t
det A
