Partial Fractions & Infinite Sums

Daniel Morales asked a few great questions from pg 573 of Larson (infinite series).

Most of his questions (#27-28, 33-36) have to do with partial fractions.  Here is a quick review if you have forgotten how to do partial fractions.  Its very useful for taking a rational expression and ‘breaking’ it into smaller terms that are easier to work with, compute or cancel out.  We will use this technique in integration and also for infinite sums.

I have worked out problem #27 in its entirety for your reference, including some notes on using the TI-89 to do sums and on partial fractions.  For part c of #27, this graphing calc image may be useful:

Larson, pg 573, #27c

Daniel also asked about problems #45-46.  These are actually just infinite geometric series (from Algebra II). You can break the sum into smaller sums to find its value.  Here is the solution to #45:

Infinite Geometric Series

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