Mathematical Methods in the Physical Sciences/Chapter 1/Section 2

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Overview

This is a notation chapter. You're simply becoming more familiar with the terminology and notation of infinite series.

The <math>\sum</math> symbol may be new. Well, it's no longer new after this chapter. Get used to it. It is going to be your best friend for a long time.

Problems

1

2

The <math>(-1)^n</math> is the secret sauce for how to get alternating terms. Be careful: if the 1st term is positive, then you need <math>-1(-1)^n</math> or <math>(-1)^{n+1}</math>.

3

4

5

6

7

8

When you have consecutive multiplied numbers, then factorials could be involved.

Note that <math>5!/3!</math> is simply <math>5 \cdot 4</math>. The 3, 2, 1 terms disappear by dividing by <math>3!</math>.

Of course, you can always do <math>(n+1)(n)(n-1)</math> or something similar, but I think factorials are cooler.

9

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11

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