elemento finito

>> A = [-9.4 40 0; 40 -169.4 0; 0 0 -109.4];

>> B = [0; 0; 0];

>> X=A\B

X =

0

0

0

>> C = [0; 0; 1];

>> Y = A/C

Error using /

Matrix dimensions must agree.

>> Y = A\C

Y =

0

0

-0.0091

>> X = rref([A B])

X =

1 0 0 0

0 1 0 0

0 0 1 0

>> [x,y,z] = solve('4*x-y+z=7','4*x-8*y+z=-21','-

2*x+y+5*z=15','x', 'y','z')

[x,y,z] = solve('4*x-y+z=7','4*x-8*y+z=-21','-

|

Error: A MATLAB string constant is not terminated properly.

>> syms x y z

>> [x, y, z] = solve ('-109.40*x+40*y+0*z=0','40*x-109.40*y+0*z=0','x^2+y^2+z^2=1','x','y','z')

x =

0

0

y =

0

0

z =

-1.0

1.0

>> [x, y, z] = solve ('-0.97*x+y+2*z=0','x-5.97*y+z=0','x^2+y^2+z^2=1','x','y','z')

x =

-0.91679204353356752808587742970032

0.91679204353356752808587742970032

y =

-0.21042290334580336618354373772874

0.21042290334580336618354373772874

z =

-0.33943268944087856802987868454028

0.33943268944087856802987868454028

>> [x, y, z] = solve ('4.851*x+y+2*z=0','x-0.149*y+z=0','x^2+y^2+z^2=1','x','y','z')

x =

0.36307100867509116902833589141457

-0.36307100867509116902833589141457

y =

-0.79746952675861704383650664593448

0.79746952675861704383650664593448

z =

-0.48189396816212510855997538165881

0.48189396816212510855997538165881

>> [x, y, z] = solve ('6.12*x+y+2*z=0','x+1.12*y+z=0','x^2+y^2+z^2=1','x','y','z')

x =

0.17067201310062551173936838430877

-0.17067201310062551173936838430877

y =

0.56707152739885250674693366399365

-0.56707152739885250674693366399365

z =

-0.80579212378734031929593408798166

0.80579212378734031929593408798166