Super Summation 8

(Of course the negative number always has to be below the sigma!) Notice how the variables m & x swap places. The variable below the sigma has to be multiplied by -1. You know that gives you a number's additive inverse, don't you?

Example:

(-3) + (-2) + (-1) + 0 + 1 + 2 + 3 + 4 + 5 = 4 + 5 = 9

[All of the additive inverses cancel each other out & you're left with 4 & 5 adding up to 9! Just below is the negative version of this summation!]

(-5) + (-4) + (-3) + (-2) + (-1) + 0 + 1 + 2 + 3 = (-5) + (-4) = -9

The negative numbers are put in parentheses to prevent confusion with addition or subtraction.

Zero is the number of additive identity; adding it to any number gives you no change!

Here's Miss Zero Digit representing the number zero again! You may have already seen her in "Super Summation 2". This math trick is a sequel to it; plus, it's very similar to it!

By the way, the number zero is its own additive inverse, just as how the number one is its own multiplicative inverse!

Well, I guess there's no more to explain about this math trick, so I can keep this Web page short & sweet!

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