Compute the indicated products.
(i) `[[a, b],[-b ,a]][[a,-b],[b, a]]`
(ii) `[[1],[ 2],[ 3]][[2, 3 ,4]]`
(iii) `[[1,-2],[ 2 ,3]]``[[1 ,2, 3],[ 2, 3 ,1]]`
(iv) `[[2, 3 ,4 ],[3, 4 ,5],[ 4, 5, 6]][[1,-3, 5],[ 0, 2, 4],[ 3, 0, 5]]`
(v) `[[2,1],[3,2],[-1,1]]``[[1, 0, 1],[-1, 2 ,1]]`
(vi) `[[3,-1, 3],[1,0,2]]``[[2 ,-3],[ 1, 0],[ 3, 1]]`

Explanation

To compute the indicated products of the given matrices, we will follow the rules of matrix multiplication. The product of two matrices is obtained by taking the dot product of the rows of the first matrix with the columns of the second matrix. Let's solve each part step by step.

### (i) Compute `[[a, b],[-b ,a]][[a,-b],[b, a]]`

1. **Identify the matrices**:
- First matrix: \( M_1 = \begin{bmatrix} a & b \\ -b & a \end{bmatrix} \)
- Second matrix: \( M_2 = \begin{bmatrix} a & -b \\ b & a \end{bmatrix} \)

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