Sal takes the mystery out of the trigonometric identities by showing how easily they can be derived. He continues with a problem he started in the video �Trig identities part three (part five if you watch the proofs) and proves the trig...

In this part two video, Sal finishes the trigonometric word problem of the wayward ship captain. He wisely continues the algebra work on the problem before finally turning to his calculator for the very last calculation.

In this video, Sal shows how the sine and cosine of an angle are defined on the unit circle. He inscribes a 30-60-90 triangle in the unit circle and explains how one can use SOH-CAH-TOA to find the coordinates on the circle.

Sal starts to solve a trigonometric word problem of a wayward ship captain who veers off course and once aware of his predicament, needs to know how far he is from his destination. Instead of using the Law of Cosines in his solution, Sal...

Sal solves a challenging problem that consists of a system of three trigonometric equations and three unknowns.

In this video, Sal reviews the basic trigonometric definitions and identities including the sum of angles formulas and then derives the double angle formulas.

Sal proves the sum of angles formula for sine, sin (a+ b) = cos (a) sin (b) + sin (a) cos (b), through a clear but rather non-intuitive proof. The proof is interesting as it not only uses the SOH-CAH-TOA model but requires one to recall...

Using a similar method that he used to prove the sum of angles formula for sine, Sal shows the proof of the cosine sum of angles formula, cos (a+ b) = cos (a) cos (b) - sin (a) sin (b). This proof also uses the SOH-CAH-TOA model and some...

In this introductory video, Sal defines polar coordinates and using basic trigonometry identities and the Pythagorean Theorem defines the relationships between Cartesian coordinates and polar coordinates.

If solving trigonometric equations is your idea of fun, then this video is correctly titled. Here Sal uses trigonometric identities, the quadratic formula, and inverse trigonometric functions to solve a trigonometric equation sent in by...

Sal solves a challenging trigonometric problem for finding the number of values of _ that satisfy a number of constraints over a given interval. He shows a clear step-by-step solution and uses some trigonometric identities that he derives.

Sal solves an interesting question in this video from a college entrance exam in India that requires one to use knowledge of arithmetic progressions, trigonometric identities, and algebra. He works through solving the problem in a...

In the third video on inverse trigonometric functions, Sal follows a format similar to the last two. He finds the value for the arcos (-1/2) and shows the restricted domain of the arccos function. He also finds the value for cos(arccos...

Continuing with inverse trigonometric functions, Sal finds the value for tan^-1-1. He also shows the restricted domain of the arctan function.

Sal defines the concept of inverse trigonometric functions and completes two examples of arcsin. Specifically, he finds the value of the arcsin (sqroot2/2) and arcsin (sqroot3/2). He also talks about the restricted domain of arcsin...

If solving trigonometric equations is your idea of fun, then this video is correctly titled. Here Sal uses trigonometric identities, the quadratic formula, and inverse trigonometric functions to solve a trigonometric equation sent in by...

Sal continues the Ferris wheel problem in a previous video by graphing the function between zero and 30 seconds.

The next time you are at an amusement park you may want to consider all the interesting math problems you could do! Using trigonometric ratios, some logic and algebra, Sal solves a problem in this video of finding a person's height off...

In this video, Sal proves the Law of Sines by using the SOH-CAH-TOA model and setting up equivalent ratios.

Sal derives the Law of Cosines using a method similar to the wayward ship captain word problem he solves in another video. This video provides a good review of using the SOH-CAH-TOA model, the Pythagorean Theorem, some of the basic trig...

In this part 2 video, Sal finishes the trigonometric word problem of the wayward ship captain. He wisely continues the algebra work on the problem before finally turning to his calculator for the very last calculation.

Using a similar method that he used to prove the sum of angles formula for sine, Sal shows the proof the cosine sum of angles formula, cos (a+ b) = cos (a) cos (b) - sin (a) sin (b). This proof also uses the SOH-CAH-TOA model and some...

This video introduces the basics of trigonometry. It starts by defining a right triangle and showing two different examples of finding the ratios of sine, cosine, and tangent using the SOH-CAH-TOA mnemonic. This resource could be used as...

Sal defines and explains the premise of Hubble's Law and then uses trigonometry to show the relationship between velocity and distance. He explains that as the universe expands, objects get farther away from each other; as objects move...