Math 4330 Sec. 1, Matlab Assignment # 1, March 24, 2006 Name 1 ...

(a) For each δ (above) set b_e= 10^(-4)*rand(2,1); then solve A δ x δ,ǫ = b e .
(b) Consider the error obtained between x and x δǫ .
,
(c) Repeat parts (a) and (b) above withb_e= 10^(-5)*rand(2,1);
,
5. Given the matrices
solve the matrix equations:
(a) AX + B = C,
A =
[ ]
5 3
, B =
3 2
[ ]
6 2
, C =
2 4
[ ]
4 −2
,
−6 3
(b) AX + B = X,
(c) XA + B = C,
(d) XA + C = X.
6. Let A = round(10 ∗ rand(6)). Change the sixth column as follows. Set
B=A’
% (take the transpose of $A$)
now type
A(:,6)=-sum(B(1:5,:))’
(a) Explain what this last command does