how to set zoom functonality in Trusty?

Sat Apr 26 10:34:27 UTC 2014

Not need turning on the magnifier support to you see effect this keystrokes?
Be careful with following thing:
Possible only my system happening my Intel GMA X3100 video card, but if 
I turning on screen magnifier support when using GNOME Shell, Gnome 
Shell producing a crash.
After magnifier turning off GNOME Shell launching correct again.
I reported this issue with following report:
https://bugs.launchpad.net/bugs/1292357

Attila