# Science:Math Exam Resources/Courses/MATH307/April 2012/Question 03

MATH307 April 2012

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### Question 03

Suppose that A is a 3 x 4 matrix and

${\displaystyle \mathrm {rref} (A)={\begin{bmatrix}1&2&0&2\\0&0&1&2\\0&0&0&0\end{bmatrix}}}$

For each of the following, either find what is asked for, or indicate that there is insufficient information to determine it:

(i) the rank of A,

(ii) a basis for N(A),

(iii) a basis for R(A),

(iv) a basis for N(AT),

(v) a basis for R(AT).

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