# 02.06.2018: One Chapter of Math

Today's soundtrack: Elder Scrolls IV Original Soundtrack.

Chapter 4 was the largest yet, dealing with quite a few new concepts:

- Inverse operations (an operation that undoes an equation) - dividing undoes multiplication, subtracting undoes addition, etc.

- Commutative operations (switching number order in an equation without changing result). Addition and multiplication are both commutative. Subtraction and division are noncommutative.

- Associative operations (changing grouping without changing the result). Again, addition and multiplication are associative; subtraction and division are nonassociative.

- Distributive property of multiplication over addition: splitting up a multiplication problem into two easier parts, then adding the result

- Adding, multiplying, subtracting, and dividing negative numbers with or from themselves or positive numbers

- Doesn't equal, less than, greater than, less than or equal to, greater than or equal to, and approximately equals

- Exponents, square roots, and absolute values

...Phew!  