Using All 4 Aritmetic Operations on the Same Number

X + X - X × X ÷ X = X; X ≠ 0

If you use all 4 aritmetic operations on the same number, you get back to the same number!

This is true for all numbers except zero(0) since division by zero is undefined.

According to the "Please Excuse My Dear Aunt Sally" Rule, the multiplication is done first, but even if you do the addition first,...

  1. 5 + 5 = 10
  2. 10 - 5 = 5
  3. 5 × 5 = 25
  4. 25 ÷ 5 = 5

[You're back to the number you started with!]

Exponentiation is not an aritmetic operation; numbers in exponentiation problems have a "triangular" relationship. To get back to the number you started with in exponentiation, you have 2 options to choose from: radicals & logarithms. Plus, exponentiation is NOT commutative!

In other words,

XY is not always equal to YX.

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© Derek Cumberbatch