Question

For a given 2000 x 2000 matrix [A], assume that it takes about 15 seconds to find the inverse of [A] by the use of the [L][U] decomposition method, that is, finding the [L][U] once, and then doing forward substitution and back substitution 2000 times using the 2000 columns of the identity matric as the right hand side vector. The approximate time, in seconds, that it will take to find the inverse if found by repeated use of Naive Gaussian Elimination method, that is, doing forward elimination and back substitution 2000 times by using the 2000 columns