Matrices Flashcards
1
Q
Square matrix
A
Same number of rows and columns eg. 2x2
2
Q
Leading diagonal
A
elements from top left to bottom right
3
Q
Identity matrix
A
Square matric where the elements of the leading diagonal are all 1 and every other is 0
4
Q
Equal matrices
A
Same order and corresponding elements are equal
5
Q
commutative
A
A+B= B+ A
6
Q
associative
A
(A+B) + C= A+ (B+C)
7
Q
KA
A
(ka kb )
(kc kd )
8
Q
A
A
1/K (ka kb)
(kc kd)
9
Q
(A+B) - (B-C)
A
A+C
10
Q
Comfortabe Multiplication
A
2 x 2 2 x 1
2x1= order of resulting matrix
11
Q
Determinant
A
ad-bc
12
Q
Adjacent
A
d -b
-c a
13
Q
Singular
A
When determinant is 0
14
Q
Inverse
A
A−¹ = 1
—————— x Adjacent
determinant
15
Q
to test if singular
A
A-¹ A = I
(iverse x original) = Identity matrix
16
Q
A in simultaneous eqns
A
Coeff
17
Q
X in silmultaneous
A
variables
18
Q
B
A
answer
19
Q
A X =
A
B
20
Q
X =
A
= A-¹ x B
