Examples of using Trig functions in English and their translations into Thai
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Ecclesiastic
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Ecclesiastic
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Trig Functions.
So let's figure out the trig functions for that angle x.
Well, we could break out the unit circle definition of our trig functions.
So which of the trig functions uses the opposite and the adjacent?
We will try to do stuff with polynomials and trig functions as well.
Now let's do the other trig functions or at least the other core trig functions.
Well to answer this you just have to remember the definitions of the trig functions.
And now I will just do the basic trig functions, and you should memorize these as well.
Because that's a very useful limit to know later on when we take the derivatives of trig functions.
Now let's find the trig, let's find the trig functions for this angle up here.
Like some trig identities that I'm familiar with, so maybe I can substitute with trig functions.
In this presentation we're going to learn how to graph trig functions without having to kind of graph point by point.
And even these, I also have proofs to show you how to get these from just the basic definitions of your trig functions.
And then once I have right triangles, then now I can start to use trig functions and the Pythagorean theorem, et cetera, et cetera.
These are the circular trig functions, you give me a t on these parameterizations we end up on the unit circle!
And we just kind of chugged through it using SOHCAHTOA and just our very simple trig functions, and we got the right answer.
So the trig functions tell you that for any angle, it tells you what the ratios of the sides of the triangle are relative to that angle.
And we will see that there are other trig ratios, but they can all be derived from these three basic trig functions.
So on the trig. functions, this is the unit circle definition of the trig functions, this is a nice review of all of that.
And if any of this is confusing, review the video where I use the unit circle to solve the various values of the trig functions and then this should make sense.
I like to keep it in kind of the fundamental trig functions, or trig ratios as opposed to things like secant and cosecant.
You know, when you're 40 years old, you probably won't have the law of cosines still memorized, but if you have that ability to start with the trig functions and just move forward, then you will always be set.
Our new definition of the trig functions was that sine of theta is equal to the y-coordinate, right, this is y-coordinate where it intersects the unit circle.
Wouldn't it be neat if there were an analogy here; over here you pick any t based on our circular trig functions, you ended up with a point on the unit circle.
So if you're trying to find the trig functions of angles that aren't part of right triangles, we're going to see that we're going to have to construct right triangles, but let's just focus on the right triangles for now.
So let's draw ourselves a unit circle because we're going to have to use the unit circle defnition of trig functions to come up with what the sine and cosecante of -210 degree are.
That there is this relationship here there is this relationship between these trig functions and the unit circle, here between our newly defined hyperbolic trig functions and the unit hyperbola.
Well the most basic trig identity, and this comes out of the unit circle definition of trig functions, is that sine squared x plus cosine squared x is equal to 1.
I don't want to confuse you too much, but I just want to show you that when you take the trig functions, it matters which angle of the right angle you're taking the functions of.
Okay, so which trig function relates opposite and adjacent?