# Easy matrix question

• Mar 25th 2010, 10:52 AM
craig
Easy matrix question
Hi just a quick question.

I have a matrix $A$, and the inverse of this matrix, $A^{-1}$ is equal to the original, ie., $A = A^{-1}$.

What is the name for these type of matrices?

Thanks
• Mar 25th 2010, 11:09 AM
thepartymushroom
according to wikipedia:

"A matrix that is its own inverse is called an involution."
• Mar 25th 2010, 11:13 AM
craig
Thank you!