The length of my practice bruh, anyways feel free to ask if you don’t get some parts of it.
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I legit just asked my teacher what a polar coord was.
Yeah, uhm… she doesn’t know much either, she looked it up and gave me this equation:
x = r cos phi sin theta
y = r sin phi cos theta
z = r cos theta
Where theta and phi are random angles between 0 and two PI.
Now I’m confused 
Also, why sines and cosines?
Why do they come into play, they are for triangles… right?
I think so? I’ve only heard them in use with triangles
I think you can also use triangles inside of triangles (or vice versa)…
Well theta is like a placeholder, no clue what the heck phi is though
I think it’s the other way around, but IDK 
Theta is an unknown angle in a triangle (And now apparently a circle)
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Aha! I expected you to to say like this. like you know the radius of one circle is equal no matter how you measure it (as long as as you start it from the middle of the circle)
In trigonometry and going with pythagoras, this always will be one number (aka 1), i’m using 0 instead of the sign for degrees.
sqrt(sin(0)^2+cos(0)^2)
just like the circle itself, you even can draw a circle using loop and sin and cosine as well.
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And this is 0:44 AM here, goodnight 
Your doing math now than??? Wow!
Hey guys!
I finally have time to come back and help out 
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?
You got me confused.
Huh, ok I didn’t know that sine and cosine are used in circles (I looked at mathsisfun.com again and saw that they can - I used them to calculate the third side of a triangle - plus tan).
I’m still confused tho…
Why does the pythagorean theorem come in here? Also, why sqrt(sin(0) ** 2 + cos (0) ** 2)? I don’t get the relation
Also, wdym “this always will be one number (aka 1), i’m using 0 instead of the sign for degrees”?
The 0 there supposed to be the sign of the angle (I clearly forgot the “angle” word last night).
Still, the radius of the unit circle is 1, and if a circle’s radius is more or less than it (<0), we only need to multiply the radius to the result of cos and sin.
But why Pythagorean theory?
It says that sqrt(a ^ 2 + b ^ 2) equals to the chord of the triangle (it must have a 90 angle)
The radius value of a circle is always same from the middle to its circumference, like this
The black line is a chord, and since the radius is always one value, the chord will still be the same size. that’s why this statement above is true:
sqrt( sin(a) ^ 2 + cos(a) ^ 2 ) * radius == radius
If it was not true then you couldn’t make points on the surface of sphere.
Yeah, basically because I’ve no motivation in daytime.
I love how this topic started as a celebration then moved to general discussion and now is a personal help service between @anon19508339 @Thewebuser22 
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Shd reclassify as hosting/coding + maths support???
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This is an informal topic, so I don’t really mind.
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If it isn’t true then it wouldn’t be a circle, either.
Yeah, I found out that a triangle can make a circle if you increment the value of the angle and redraw every time.
Now I got to learn how to use quaternions and mutate vectors and Eulers so my camera can constantly stay behind an object…
All I know is
1 × i = i
i × i = −1
−1 × i = −i
−i × i = 1
And that i = the square root of -1.
Quaternions won’t be easy 
What are they even for?
Rotation? Movement? Or both…?
I do not really understand anything about root of negative numbers. However anything regarding the 3d world, 3d in 2d rendering and etc has to do with trigonometry and the math of circles.
Since I have not done anything regarding this since 10months ago, I almost have forgoten its formula.
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