initial commit / add all books

1 files changed, 45 insertions, 0 deletions

diff --git a/26/CH2/EX2.5.1/2_5_1.sce b/26/CH2/EX2.5.1/2_5_1.sce
new file mode 100755
index 000000000..591f40ab1
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+++ b/26/CH2/EX2.5.1/2_5_1.sce
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+disp('the lower triangular matrix is:')

+L=[1 0 0;-1 1 0;2 -5 1];

+disp(L)

+disp('the upper triangular matrix is:')

+U=[3 -7 -2;0 -2 -1;0 0 -1];

+disp(U)

+disp('the RHS of the equations are')

+b=[-7;5;2];

+disp(b)

+disp('combining matrices L and b')

+c=[L b];

+disp(c)

+disp('performing row operations')

+disp('R2=R2+R1')

+c(2,:)=c(2,:)+c(1,:)

+disp(c)

+disp('R3=R3-2*R1')

+c(3,:)=c(3,:)-2*c(1,:)

+disp(c)

+disp('R3=R3+5*R2')

+c(3,:)=c(3,:)+5*c(2,:)

+disp(c)

+y=c(:,4)

+disp(y,'y=')

+disp('combining U and y')

+d=[U y];

+disp(d)

+disp('performing row operations')

+disp('R3=R3/-6')

+d(3,:)=d(3,:)/(-1)

+disp(d)

+disp('R2=R2+R3 and R1=R1+2*R3')

+d(2,:)=d(2,:)+d(3,:)

+d(1,:)=d(1,:)+2*d(3,:)

+disp(d)

+disp('R1=R1-3.5*R2')

+d(1,:)=d(1,:)-3.5*d(2,:)

+disp(d)

+disp('R1=R1/3 and R2=R2/-2')

+d(1,:)=d(1,:)/3

+d(2,:)=d(2,:)/(-2)

+disp(d)

+disp('the solution is:')

+x=d(:,4)

+disp(x,'x=')
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