Science:Math Exam Resources/Courses/MATH221/April 2008/Question 06 (a)

MATH221 April 2008

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Question 06 (a)
Consider the homogeneous system $\displaystyle A{\vec {x}}=0$. Suppose that the Echelon form of A is given by $\displaystyle A_{1}={\begin{bmatrix}1&0&-1&2\\0&0&0&0\\0&0&0&0\end{bmatrix}}$ What is the rank of A

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Hint

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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. The rank is the number of nonzero rows in the rref. We are given the rref and can see that the rank is 1.