Software update slows start up
As a result of a software update prompt, I recently updated to Yosemite 10.10.3 and installed Yosemite Recovery Update version 1.0. Now my MacBook Pro 13 inch, which is less than a year old, is very slow to boot up. It did not have this problem before the update. What is causing this and how do I fix it?
iMac, Mac OS X (10.6.8)