Suppose that limx->c f(x) = infinity and limx->c g(x)=l where l is a real number. Prove the following.(adsbygoogle = window.adsbygoogle || []).push({});

limx->c[f(x)+g(x)]= infinity

limx->c[f(x)g(x)]= infinity if l > 0

limx->c[f(x)g(x)]= -infinity if l < 0

I have the proof for these already, but I couldn't understand them, would someone please explain them.

The thing I don't understand is where does the L come from, but explanation in general would be greatly appreciated

Here is the proof for the second one:

[URL=http://imageshack.us/photo/my-images/190/unledmkd.png/][PLAIN]http://img190.imageshack.us/img190/2665/unledmkd.png[/URL]

Uploaded with ImageShack.us[/PLAIN]

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# Need help Proving infinite limit properties.

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