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Proof: Law of Sines, Trig Identities and Examples, Trigonometry Instructional VideoProof: Law of Sines, Trig Identities and Examples, Trigonometry Instructional Video
Publisher
Khan Academy
Resource Details
Curator Rating
Educator Rating
Not yet Rated
Grade
11th - Higher Ed
Subjects
Math
2 more...
Resource Type
Instructional Videos
Media Length
6:34
Audiences
For Teacher Use
1 more...
Duration
10 mins
Instructional Strategies
Flipped Classroom
1 more...
Accessibility
Closed Captions
1 more...
Year
2007
Usage Permissions
Creative Commons
BY-NC-SA: 3.0
cc
Instructional Video

Proof: Law of Sines, Trig Identities and Examples, Trigonometry

Curated and Reviewed by Lesson Planet
This Proof: Law of Sines, Trig Identities and Examples, Trigonometry instructional video also includes:
  • Proof: Law of Sines (HTML version from khanacademy.org)
  • Join to access all included materials

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

30 Views 21 Downloads

Concepts

law of sines, Trigonometry

Additional Tags

law of sines, Trigonometry, finding sides or angles of any triangle, math

Classroom Considerations

  • This video is hosted on YouTube

See similar resources:

Instructional Video

Introduction to the Unit Circle, Trigonometry

Khan Academy
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 to use SOH-CAH-TOA to find the circle's coordinates.
9 mins 10th - 12th Math
Instructional Video

Trigonometry Word Problems (Part 1)

Khan Academy
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...
10 mins 10th - 12th Math
Instructional Video

Intro to the Trigonometric Ratios

Curated OER
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...
9 mins 11th - Higher Ed Math
Instructional Video

Proof of the Law of Cosines, Trig Identities and Examples, Trigonometry

Khan Academy
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 basic trig...
9 mins 11th - Higher Ed Math
Instructional Video

Ferris Wheel Trig Problem

Khan Academy
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...
7 mins 10th - Higher Ed Math
Instructional Video

Trigonometry work problems (part 2)

Curated OER
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.
3 mins 11th - Higher Ed Math
Instructional Video

Trigonometry Work Problems (Part 2)

Curated OER
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.
3 mins 10th - 12th Math
Instructional Video

Proof: cos(a+b)=(cos a)(cos b)-(sin a)(sin b)

Curated OER
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...
9 mins 11th - Higher Ed Math
Unit Plan

Ck 12: Trigonometry: Law of Sines

CK-12 Foundation
[Free Registration/Login may be required to access all resource tools.] Learn how to use the Law of Sines with different types of triangles.
10th - 12th Math
CCSS: Designed
Instructional Video

What is the Law of Sines?

Curated OER
The Law of Sines is derived in this video by using formula for the area of a triangle that multiplies _ times two adjacent sides and the sine of their included angle.
6 mins 10th - 11th Math
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