Pure: Matrices Flashcards
What does the matrix representing a stretch parallel to the x-axis with scale factor k look like?
2x2
k 0
0 1
What does the matrix representing a stretch parallel to the y-axis with scale factor k look like?
2x2
1 0
0 k
What does the matrix representing an enlargement, centre the origin, with scale factor k look like?
2x2
k 0
0 k
What does the matrix representing a rotation 90° anticlockwise about the origin look like?
2x2
0 -1
1 0
What does the matrix representing a rotation 180° about the origin look like?
2x2
-1 0
0 -1
What does the matrix representing a rotation 90° clockwise about the origin look like?
2x2
0 1
-1 0
What does the matrix representing an anticlockwise rotation through any angle θ look like?
2x2
cosθ -sinθ
sinθ cosθ
What does the matrix representing a reflection in the x-axis look like?
2x2
1 0
0 -1
What does the matrix representing a reflection in the y-axis look like?
2x2
-1 0
0 1
What does the matrix representing a reflection in the line y = x look like?
2x2
0 1
1 0
What does the matrix representing a reflection in the line y = -x look like?
2x2
0 -1
-1 0
What does the matrix representing a shear parallel to the x-axis with factor k look like?
2x2
1 k
0 1
What does the matrix representing a shear parallel to the y-axis with factor k look like?
2x2
1 0
k 1
What does the matrix representing a reflection in the plane x = 0 look like?
3x3
-1 0 0
0 1 0
0 0 1
What does the matrix representing a reflection in the plane y = 0 look like?
3x3
1 0 0
0 -1 0
0 0 1