โฌ Matrix Transformations
Edit the 2ร2 matrix entries and watch the coordinate grid transform in real time. Rotate, scale, shear, reflect โ see eigenvectors glow as they stay on their lines, and watch the determinant measure the area change.
How to read this
The light grey grid shows the original coordinate system. The coloured grid shows the same grid after the matrix transformation. The red arrow is the transformed รฎ = (1,0) basis vector; the blue arrow is ฤต = (0,1). Eigenvectors (yellow) are special vectors that only stretch or flip โ they never rotate.
Key concepts
A 2ร2 matrix
M = [[a,b],[c,d]] transforms
every point (x,y) โ (ax+by, cx+dy). The
determinant det(M) = adโbc
measures how area changes: det=1 preserves area, det=โ1 reflects,
det=0 collapses space to a line (or point).
Eigenvalues ฮป satisfy Mv =
ฮปv โ the matrix only stretches the eigenvector by ฮป, never rotates
it. Real eigenvalues exist when the discriminant (traceยฒ โ 4ยทdet) โฅ
0. ฮป = (trace ยฑ โ(traceยฒโ4ยทdet)) / 2.