Those are trigonometric functions. The use cases are as plenty as there are use cases for addition and subtraction. You will most likely learn these functions in a trig or pre-calculus class.

Figure A:

Figure B:

Here I’m just going to talk about sine and cosine + their inverse functions asin and acos (`math.sin`

and `math.cos`

+ `math.asin`

and `math.acos`

). It’s helpful to think about sine and cosine as the Y and X coordinates on a plane as Θ (theta) increases. In figure B, you can see the graph of `y = sin(Θ)`

depicted by the red line and the graph of `x = cos(Θ)`

in blue. It also shows you how that translates into coordinates on a plane. If you calculate x and y for every number between 0 and 2 * pi, it will result in a circle! You can graph the functions `y=cos(x)`

and `y=sin(x)`

from 0 to 2π on Desmos and convert the two values into X and Y coordinates if figure is confusing to you.

Tangent is the ratio between sine and cosine `tan(Θ) = sin(Θ) / cos(Θ)`

. Often times it can be represented as the “slope”; the “instantaneous tangent line” is something you learn how to calculate in a calculus class with limits and derivatives. Don’t worry too much about this one until you grasp the concept of sine and cosine first.

`math.asin`

and `math.acos`

do the opposite (inverse) of `math.sin`

and `math.cos`

. They return the Θ value that corresponds to the number from -1, 1 you pass in. I wouldn’t worry too much about those right now though. If you have any questions, feel free to ask them here.