Please choose the correct ending to complete the given sentence: Education and Communications: [header] How to find the inverse of a matrix [title] Make sure your matrix is square. [step] A matrix can have an inverse matrix only if its number of columns is equal to its number of rows. If your matrix is not square, there is no inverse.

Ending1: [substeps] If a row is square but yet it has so many rows, it can be represented as a multiplication matrix. The matrix should not have one row or column; it should have two columns. Ending2: [substeps] The quinvon80 matrix is square, but it does not have rows. [title] Use multiplier to determine a matrix's length. Ending3: [substeps] Instead, your matrix's number of columns is equal to the number of columns it contains. For example, a 3-column matrix contains 102x104 columns and so a 10-column matrix contains 152x104 columns. Ending4: [title] Check whether your matrix is 2x2. [step] If your matrix has 2 rows and 2 columns, you can find its inverse directly with this method.

Answer format: ending1/ending2/ending3/ending4