A use Gauss-Jordan elimination (with no row exchanges) to find A−1.

I'm sorry, but you didn't provide a specific matrix A to find the inverse of. The Gauss-Jordan elimination method involves creating an augmented matrix with the given matrix and the identity matrix, then using row operations to transform the given matrix into the identity matrix. The identity matrix will then transform into the inverse of the given matrix. However, without a specific matrix A, I can't provide a step-by-step solution.