Science:Math Exam Resources/Courses/MATH152/April 2011/Question A 07

MATH152 April 2011

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Question A 07
Write the matrix A that would result from the following lines of MATLAB code: A = zeros(3,2); A(1,1) = 5; A(2,2) = 3; A(3,1) = 1;

Make sure you understand the problem fully: What is the question asking you to do? Are there specific conditions or constraints that you should take note of? How will you know if your answer is correct from your work only? Can you rephrase the question in your own words in a way that makes sense to you?

If you are stuck, check the hint below. Consider it for a while. Does it give you a new idea on how to approach the problem? If so, try it!

Hint
Matlab stores entries in rows then columns. Therefore A(i,j)=1 would put a 1 in the ith row and jth column.

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Solution

Found a typo? Is this solution unclear? Let us know here. Please rate my easiness! It's quick and helps everyone guide their studies. From the hint we know that Matlab stores by row then by column. Therefore the first line of code A=zeros(3,2); would create a matrix of zeros with 3 rows and 2 columns, $A={\begin{bmatrix}0&0\\0&0\\0&0\end{bmatrix}}.$ The next lines of code A(1,1)=5; A(2,2)=3; A(3,1)=1; would put a 5 in the 1st row, 1st column, a 3 in the 2nd row, 2nd column and a 1 in the 3rd row, 1st column and therefore, $A={\begin{bmatrix}5&0\\0&3\\1&0\end{bmatrix}}$ is our created matrix.