>> A = [2 -1 3; 4 -2 1; 0 3 1] A = 2 -1 3 4 -2 1 0 3 1 >> r = [1 5 -3]' r = 1 5 -3 >> x = A \ r x = 1.0000 -0.8000 -0.6000
>> A*x - r ans = 1.0e-15 * -0.3331 0 0
A=rand(1000); r = rand(1000,1); x = A \ r;
>> error = max(abs(A*x-r)) error = 2.0761e-13
>> roots(poly1) ans = 4 -3
>> poly2 = [1 0 1]; >> roots(poly2) ans = 0 + 1.0000i 0 - 1.0000i
>> poly3 = [1 -8 20 -10 -25 22]; >> roots(poly3) ans = 3.7059 -1.0781 2.1861 + 0.8527i 2.1861 - 0.8527i 1.0000
>> F = @(x) sin(x) - exp(-0.05*x.^2) F = @(x)sin(x)-exp(-0.05*x.^2)
>> x0 = 0; >> x = fzero(F, x0) x = 1.1968
x0 | x |
---|---|
0 | 1.1968 |
1 | 1.1968 |
2 | 2.2537 |
3 | 2.2537 |
4 | 2.2537 |
5 | 6.4116 |
x = -15:0.1:15; plot(x, F(x), [-15 15], [0 0])