Is there a way to use 2 seperate Id's on my ipad2


Is there a way to use 2 seperate Id's on my ipad2
My wife purchased a book on her Iphone4 and wants to read it on the ipad2 so it has larger font. I have my apple id on the ipad but i dont want to loose all of the stuff I already have on it. Is there a way to use 2 seperate apple Id's on one ipad2?
Doesn't this lock the user out of their own account now or am I missing on this associated devices stuff?
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Your Apple ID can have up to 10 devices and computers (combined) associated with it. Each computer must also beauthorized using the same Apple ID. Once a device or computer is associated with your Apple ID, you cannot associate that device or computer with another Apple ID for 90 days. You can view which devices or computers are currently associated, remove unused devices or computers, and see how long before they can be associated with a different Apple ID from the Account Information page in iTunes on your computer:
Message was edited by: Demo
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