a) Given that: A=\left(\begin{array}{cc}

7 & -2 \\

6 & 1 \\

5 & -8

\end{array}\right) \quad B=\left(\begin{array}{ccc}

4 & 2 & -3 \\

-5 & -4 & -1

\end{array}\right) \quad D=\left(\begin{array}{ccc}

-3 & 6 & 9 \\

5 & -7 & 2 \\

4 & -6 & 1

\end{array}\right) Find 2(A - B")" Calculate Dx A \text { Given that } E=\left(\begin{array}{ccc}

5 & 4 & 7 \\

2 & 3 & -2 \\

-4 & 9 & -3

\end{array}\right) i) Find cofactor of elements e11, e12 and e13 \text { i) Find cofactor of elements } e_{11}, e_{12} \text { and } e_{13} \text { ii) Find the } \operatorname{det}(E) c) Use the Gaussian elimination (matrix) method to solve the following equations: X + y - z = 4 X - 2y + 3z = -6 2 x +3y + z = 7 i) Find the Eigenvalues and Eigenvectors of the following equations: 7x - 8y = 0 -10x + 9y = 0 ii) State the Characteristic Equation of the Eigenvalues. The coordinates of points A and B are as follows: А(3, -4) and B %3 (-1, 5) \text { Determine the position vectors of } \vec{A}, \vec{B} \text { Determine } \vec{B} A \text { and }|B A| )Find the cosine angle in degrees between vectors B and AB \text { Integrate and simplify the following function: } y=\int-4 x \ln \left(x^{2}\right) d x