What does RREF stand for?

RREF stands for Reduced Row Echelon Form. This is a specific form of a matrix used in linear algebra that simplifies matrices to facilitate solving systems of linear equations. In RREF, each leading entry in a non-zero row is 1, each leading 1 is the only non-zero entry in its column, and the leading 1s move to the right as you move down the rows of the matrix. This format is particularly useful because it allows for easy back substitution to find solutions to equations.

The other options do not accurately capture the meaning of RREF. Regular Row Echelon Form is a related but different concept which does not require the leading 1s to be the only non-zero entries in their respective columns. Similarly, the terms Rapid Row Elimination Format and Random Row Echelon Form do not represent standard terminologies in linear algebra.