# Automatically breaking formulas [duplicate]

Possible Duplicate:
How can I split an equation over two lines

I am trying to compile my papers into Kindle readable PDF files. I can get pretty good outputs by just changing the height and the width of the document. One problem is formulas run out of the page and I cannot really adjust them manually for hundreds of formulas. I am wondering if there is any package that automatically breaks a formula if it runs out of the page margins.

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