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What is a Cosine. Explains what a cosine is and why it matters. What is a Sine. Explains what a sine is and why it matters. Trigonometry Laws and Identities Math Sheet. This trigonometry laws and identities help sheet contains the law of cosines, law of sines, and law of tangents. It also contains the following identities: A helpful scientific calculator that runs in your web browser window. Resources Math Trigonometry Trigonometric Functions. For more information call us at: Trig Functions This website will allow students to practice identifying which trig function to use and when.

Trigonometry Terms This website will define the trig functions of sine, cosine and tangent. Computing Trigonometric Functions An overview of how to compute trigonometric functions Clark University. Trigonometric functions and their inverses Explains how we can use the unit circle to find the trig functions for any angle, explains inverse functions, and how to graph them.

What is a Tangent Explains what a tangent is and why it matters. What is a Cosine Explains what a cosine is and why it matters. What is a Sine Explains what a sine is and why it matters. To find this angle for this problem all we need to do is use a little geometry.

As the discussion about finding the second angle has shown there are many ways to write any given angle on the unit circle. This is very easy to do. The same thing can be done for the second solution. So, we will start out with the list of all possible solutions from the previous problem.

This one is very similar to Problem 1, although there is a very important difference. So, what are these angles? Now we come to the very important difference between this problem and Problem 1.

The solution is NOT. Note the difference in the arguments of the sine function! This makes all the difference in the world in finding the solution! Therefore, the set of solutions is. However, it makes the point. However, most of the problem is identical.

In this case the solutions we get will be. Notice the difference in the left-hand sides between this solution and the corresponding solution in the previous problem. They will on occasion and you need to get used to seeing them. Note as well that it is possible to have one of these be a solution and the other to not be a solution.

It all depends on the interval being used. We would have completely missed four of the solutions! So, our solutions are. This is a trick question that is designed to remind you of certain properties about sine and cosine. This problem is a little different from the previous ones. First, we need to do some rearranging and simplification.

Again, we need to do a little work to get this equation into a form we can handle. The easiest way to do this one is to recall one of the trig formulas from the Trig Formulas section in particular Problem 3. If you divide both sides by a cosine you WILL lose solutions! Note that in this case we got a repeat answer.

So, all together we get the following solutions,. This problem appears very difficult at first glance, but only the first step is different for the previous problems. So, why cover this? Well, if you think about it there is very little difference between this and the problem you are asked to do.

First, we factor the equation. Often both will yield solutions!

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4. Identify: § · A Fourier need help with writing series is an expansion of a periodic function f(x) in terms of an infinite sum of sines and cosines. Trigonometry homework help for interval.

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Mar 23,  · Physics Forums | Science Articles, Homework Help, Discussion. Forums > Homework Help > Precalculus Mathematics Homework > Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors. Homework Help: Finding intervals of trig functions Mar 21, #1. steve snash. 1. The problem statement, all variables and given/known.