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sara_87
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Question 1:
Solve the system of equations
-w + 3x - 2y + z = 1
w + 2x - 4y - 3z = 2
x + 2y + z = 4
2w + 3x - y - z = 7
The attempt at a solution
To do this in matlab, this is what I will did:
>> A=[-1,3,-2,1;1,2,-4,-3;0,1,2,1;2,3,-1,-1]; b = [1;2;4;7]
>>x=inv(A)*b
Then MATLAB should give an answer with the solutions of w, x, y and z written in a separate line…no?
Question 2:
Find the eigenvalues and eigenvectors of the matrix
3, -1, 0, 0
-1, 5, -2, 0
0, -2, 6, -1
0, 0, -1, 2
The attempt at a solution
In MATLAB do I do this:
>>A=[3,-1,0,0;-1,5,-2,0;0,-2,6,-1;0,0,-1,2] ;
>>[V,D]=eig(A)
Then I should get an answer for V and D, and v is a matrix whose columns are the eigenvectors and D is the diagonal matrix, so we multiply the first column of V with the first diagonal of D etc… am I wrong?
Question 3:
Let
A=
-3, 4, 2, 0
1, -2, 0, 1
-4, 5, 0, 3
0, 1, -4, 2
Write the Matlab commands to construct the following matrix:
3, 0, 0, 0, -3, 1, -4, 0
0, 4, 0, 0, 4, -2, 5, 1
0, 0, 5, 0, 2, 0, 0, -4
0, 0, 0, 6, 0, 1, 3, 2
-3, 4, 2, 0, 5, 5, 5, 5
1, -2, 0, 1, 5, 5, 5, 5
-4, 5, 0, 3, 5, 5, 5, 5
0, 1, -4, 2, 5, 5, 5, 5
The attempt at a solution
In MATLAB should i do this:
>>A=[-3,4,2,0;1,-2,0,1;-4,5,0,3;0,1,-4,2]
Then to construct the other big matrix do I do this:
>> B=[diag(3:6),A’;A, fives(4,4)]
You’ve probably all figured that I don’t have access to MATLAB just now, so I would be grateful if someone who has access to MATLAB could just copy and paste the commands into see if it works.
Also between each question do I write clear all to clear everything before I start the question?
Solve the system of equations
-w + 3x - 2y + z = 1
w + 2x - 4y - 3z = 2
x + 2y + z = 4
2w + 3x - y - z = 7
The attempt at a solution
To do this in matlab, this is what I will did:
>> A=[-1,3,-2,1;1,2,-4,-3;0,1,2,1;2,3,-1,-1]; b = [1;2;4;7]
>>x=inv(A)*b
Then MATLAB should give an answer with the solutions of w, x, y and z written in a separate line…no?
Question 2:
Find the eigenvalues and eigenvectors of the matrix
3, -1, 0, 0
-1, 5, -2, 0
0, -2, 6, -1
0, 0, -1, 2
The attempt at a solution
In MATLAB do I do this:
>>A=[3,-1,0,0;-1,5,-2,0;0,-2,6,-1;0,0,-1,2] ;
>>[V,D]=eig(A)
Then I should get an answer for V and D, and v is a matrix whose columns are the eigenvectors and D is the diagonal matrix, so we multiply the first column of V with the first diagonal of D etc… am I wrong?
Question 3:
Let
A=
-3, 4, 2, 0
1, -2, 0, 1
-4, 5, 0, 3
0, 1, -4, 2
Write the Matlab commands to construct the following matrix:
3, 0, 0, 0, -3, 1, -4, 0
0, 4, 0, 0, 4, -2, 5, 1
0, 0, 5, 0, 2, 0, 0, -4
0, 0, 0, 6, 0, 1, 3, 2
-3, 4, 2, 0, 5, 5, 5, 5
1, -2, 0, 1, 5, 5, 5, 5
-4, 5, 0, 3, 5, 5, 5, 5
0, 1, -4, 2, 5, 5, 5, 5
The attempt at a solution
In MATLAB should i do this:
>>A=[-3,4,2,0;1,-2,0,1;-4,5,0,3;0,1,-4,2]
Then to construct the other big matrix do I do this:
>> B=[diag(3:6),A’;A, fives(4,4)]
You’ve probably all figured that I don’t have access to MATLAB just now, so I would be grateful if someone who has access to MATLAB could just copy and paste the commands into see if it works.
Also between each question do I write clear all to clear everything before I start the question?
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