system
Given the following post, respond as if you're commenting on Reddit:
human
I’m curious about the reason of this.

I was messing around with sin, cos, and tan on a calculator and I wondered what would happen if I input 360 into them.

It came up with this:

sin(360 degrees) = 0

cos(360 degrees) = 1

tan(360 degrees) = 0

I was confused why the cosine was the only one that equaled 1 and pretty much why the whole thing was happening. Because I was confused, I asked my teacher and he responded with, “We aren’t working with angles over 90 degrees.” (which I thought was annoying) He also mentioned that it wasn’t multiplication which is also confusing.
gpt
If you start at any point on a circle, and then go 360 degrees around it, where do you end up? At the start, of course, which is the same as travelling no degrees at all. Therefore, the value of any trig function (with frequency 1) for 360 degrees is the same for 0 degrees. cos(0)=1, therefore cos(360)=1 also. Ditto for sin and tan. 

If you want to know why sin and tan are 0 at 0 and 360 degrees, look at a circle on a grid centred at the origin. If you start at the point where the circle intersects the x axis, then the cosine at that point will be 1 and the sin will be 0, because cos and sin measure the x and y coordinate of a point on the circle. tan is sin/cos, so at 0 degrees that's 0/1, which of course is 0.