I'm doing a practice exam for a math test on thursday, wondering if anyone could help figure out how to get from one step to the next. i dont think that the background info is necessary for these two steps.(adsbygoogle = window.adsbygoogle || []).push({});

the file is attached (Adobe acrobat).

what i am wondering about is the answer under (2b).

If the solution for finding (del)u(x,y) were lettered a through d (4 steps, i am wondering how the professer got from b to c.

of course i have emailed him as well.

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# Homework Help: Periodic functions

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