Apropos of Nothing (Math YouTube - for now)

So, if you take the side opposite of that second angle, divided by the hypotenuse, that always has to be the same value whenever that other angle is in your triangle.

And if there’s only one answer for that ratio given that angle, you can express the ratio as a function of the angle, since functions are just the kind of thing where each input gets exactly one output, so they’re great for representing the answers to questions with only one right answer.

So, the opposite side to an acute angle in a right triangle divided by the hypotenuse is a function of that acute angle we chose, and we call that function the “sine.”

It's Brackets (Parentheses) then Exponents then EITHER multiplication OR division depending which comes first in the equation the it's EITHER addition OR subtraction depending which comes first in the equation.

Professional-grade standards for the order of operations have different precedences for implicit multiplication (i.e. 2x) and explicit multiplication (i.e. 2 * x) and some of them would dictate that in that sort of expression, you do the implied multiplication of 2(3) = 6 before you do the division of 12 / 6 = 2, so you do get a different order than you would with PEMDAS, where it’s 12/2 = 6, 6 * 3 = 18.

That said, 2 isn’t really “the correct answer” either just because it uses a more formal or more complex set of precedence rules, people get that wrong too. The thing is, those sets of precedence rules are so rarely known that applying them in any context where you don’t know the other person is trying to use them can be risky, and lead to miscommunication.