A = matrix(QQ, [[14,5,-2],[5,5,0],[-2,0,5]])
b = matrix(QQ, [[7],[7],[3]])
C, X, D = var('C,X,D')
C = A^-1
X = A^-1*b
D = A*A^-1*b
A,b,C,X,D
( [14 5 -2] [7] [ 5/41 -5/41 2/41] [ 6/41] [7] [ 5 5 0] [7] [ -5/41 66/205 -2/41] [257/205] [7] [-2 0 5], [3], [ 2/41 -2/41 9/41], [ 27/41], [3] ) ( [14 5 -2] [7] [ 5/41 -5/41 2/41] [ 6/41] [7] [ 5 5 0] [7] [ -5/41 66/205 -2/41] [257/205] [7] [-2 0 5], [3], [ 2/41 -2/41 9/41], [ 27/41], [3] ) |
x = var('x')
solve(x^2 + 3*x + 2, x)
[x == -2, x == -1] [x == -2, x == -1] |
x, y = var('x,y')
plot3d(x^2 + y^2, (x,-2,2), (y,-2,2))
|
|
20.0/14
1.42857142857143 1.42857142857143 |
f(z) = z^5+z-1+1/z
complex_plot(f,(-5, 5), (-5,5))
|
|
|
|