How would I go about determining an orthogonal diagonalization of the following matrix?

Question

anonymous · Answer

$$A=\left[\begin{matrix}1 & 2 \ 2 & -2\end{matrix}\right]$$

anonymous · Answer

Ie, find a diagonal matrix D and an orthogonal matrix Q such that $$D=Q^{-1}AQ$$

anonymous · Answer

sorry dude, i dunno... but i tried googling... y don't u try doing the same? i found this websites. since i m clueless bout this i dunno whether these websites r relevant. http://www.physicsforums.com/showthread.php?t=219595 http://www.maths.manchester.ac.uk/~peter/MATH10212/notes10.pdf just check them out ir u oculd post in the chat box that u need help wif this... good luck!

anonymous · Answer

Cheers for that! Think I'm good with it now :)