Using Pages I'm formatting kthe copy for a textbook. I want to have the header on left pages show the book title and the header on right pages show the chapter title. is that possible on Pages?
You have the new version, so it appears it can't do what you want.
I know it's weird that an old version from 2009 can do it and the newer version can't but there's a ton of things the old Pages could do that was cut from the new version (so that it was more feature compatible with the iToys). If you need that capability, look elsewhere... or you can still buy the old (IMO, far superior) version on sites like Amazon and Ebay.
One other idea: if your textbook would be fine published to iBooks (for iPad, etc), Apple does have this (former) Pages-like software called iBooks Author that probably does what you want: http://www.apple.com/ibooks-author/ But be sure you understand it's limitations in terms of publishing options.
There's also the very popular, very specific app for book publishing called Scrivener: http://www.literatureandlatte.com/scrivener.php and I'm pretty sure it can do what you want. It has a free trial so you could verify before you buy.
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