Question

MATLAB QUESTION!!!

9) The following system of equations is used in Navier Stokes theorem to determine force fluctuations on a hypersonic jet. Solve the following system of equations using inverse matrix method and left division. Show how long this process takes to compute using Matlab. 3x+y+z+w+3v=27 5v-3y+x+7z+w=17 2x+2y-3z+4w-v=16 x+y+z+w+y=1 y-z+x-w-7v=-7

Answer 1

A=[3 1 1 1 3;1 -3 7 1 5;2 2 -3 4 -1;1 1 1 1 1;1 1 -1 -1 -7]; %%Matrix A having coefficients of x,y,z,w,v.
B=[27;17;16;1;-7]; %%RHS vector
tic %%Start time
X=inv(A)*B %%Solution using matrix inversion
toc %%End time
tic %%Start time
X1=A\B %%Solution using Left division
toc %%End time
%%Clearly left division takes lesser time.

5 A=[3 1 1 1 3;1 -3 7 1 5;2 2 -34 -1;1 1 1 1 1;1 1 -1 -1 -7]; %Matrix A having coefficients of x,y,z,w,V. B=[27;17;16;1;-7]; %%RHS vector tic %% Start time X=inv (A)*B %% Solution using matrix inversion toc %% End time tic %%Start time X1=A\B & Solution using Left division toc %%End time Clearly left division takes lesser time. 7 8 - 9 Command Window x = 11.0000 -8.0000 -4.0000 0.0000 2.0000 Elapsed time is 87 seconds. x1 = 11.0000 -8.0000 -4.0000 0.0000 2.0000 Elapsed time is 0.000239 seconds. fx >>