If `A` is `3xx4` matrix and `B` is a matrix such that `A^T B` and `B A^T` are both defined. Then, `B` is of the type `3xx4` (b) `3xx3` (c) `4xx4` (d) `4xx3`

Explanation

To determine the order of the matrix \( B \) given that \( A \) is a \( 3 \times 4 \) matrix and both \( A^T B \) and \( B A^T \) are defined, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the order of matrix \( A \)**:
- The matrix \( A \) is given as \( 3 \times 4 \).
- This means \( A \) has 3 rows and 4 columns.

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