What is the equation for average angular acceleration?

[Fed22]

I was just wondering what the equation for average angular acceleration is

At first i thought it was W avg = Delta Pheta/ Delta Time
but then i think that might be the Average Angular Speed formula...

Any ideas? i know it's a simple question so hopefully no one will get annoyed =P

 

[andrevdh]

more like

$$\alpha = \frac{\Delta \omega}{\Delta t}$$

 

[Fed22]

Thanks that helped! =)