Question

If is any noninvertible square matrix, then $\mathit{d}\mathit{e}\mathit{t}\mathit{A}\mathbf{=}\mathit{d}\mathit{e}\mathit{t}\mathbf{\left(}\mathit{r}\mathit{r}\mathit{e}\mathit{f}\mathit{A}\mathbf{\right)}$.

Short answer

Therefore,

$detA=det\left(rrefA\right)$

Yes, the given statement is true.

Step-by-step solution

Orthogonal Matrix Definition. 

A square matrix with real numbers or elements is said to be an orthogonal matrix, if its transpose is equal to its inverse matrix.

Or we can say, when the product of a square matrix and its transpose gives an identity matrix, then the square matrix is known as an orthogonal matrix.

To check whether the given condition is true or false.

Given condition,

$detA=det\left(rrefA\right)$.

If is a non-invertible matrix,

Then

det A = 0.

$\det A=\mathrm{detrref}A$

Therefore, the given condition satisfied. So, the given statement is true.