Week 3 (matrices and inverse) Flashcards
(8 cards)
1
Q
3x3 determinants
A
Its just the cross products
2
Q
3x3 inverse
A
- find the determinant
- Find M, which has the cross product in each of there positions a1,a1, covers the first row and column
- Find C, which is just negative M in come spots
- Find C transpose, first column becomes first row
- 1/(det) * C transpose
3
Q
rotation matrix
A
cos(x) -sin(x)
sin(x) cos(x)
4
Q
reflection in y axis
dilation in y axis
A
-1 0
0 1
a 0
0 1
5
Q
reflection in x axis
dilation in x axis
A
10
0-1
10
0a
6
Q
shear
A
1a
01
7
Q
vector projection
A
b1^2 b1b2
b1b2 b2^2
8
Q
y = x
A
01
10
