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!
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