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Proof of the Law of Cosines, Trig Identities and Examples, Trigonometry Instructional VideoProof of the Law of Cosines, 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
9:27
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 of the Law of Cosines, Trig Identities and Examples, Trigonometry

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

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 identities, and algebra.

19 Views 12 Downloads

Concepts

law of cosines, Trigonometry

Additional Tags

law of cosines, Trigonometry, law of cos, finding sides or angles of any triangle, math

Classroom Considerations

  • This video is hosted on YouTube

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Lesson Plan

Law of Cosines

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Worksheet

Inverse Trig Functions

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Learners solve and graph 10 different problems that are the inverses of various trig functions. First, they determine which equation is equivalent to a given equation. Then, they find an angle of a right triangle, given its leg lengths....
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Lesson Plan

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In this math worksheet, students are given 7 problems in which they write expressions for trig functions, compute limits and graph functions.
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Instructional Video

Trigonometric Ratios with a Calculator: Lesson

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Calculators ... they are more efficient than tables. Using two 30-60 right triangles, the segment of a playlist on geometry shows that trigonometric ratios for an angle are the same independent of the size of the triangle. The video...
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IIT JEE Trigonometric Constraints, Trig Identities and Examples, Trigonometry

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Sal solves a challenging trigonometric problem for finding the number of values of _ that satisfy several constraints over a given interval. He shows a clear step-by-step solution and uses some trigonometric identities that he derives.
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Trig Identities Part 3 (Part 5 If You Watch the Proofs), Trigonometry

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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...
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Instructional Video

The Trigonometric Ratios: Lesson

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SOH, what is this thing called trigonometric ratios? A section of an extensive playlist on geometry identifies the adjacent and opposite sides in relationship of an angle. Using the identified sides, the video defines the sine, cosine,...
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IIT JEE Trigonometry Problem 1, Trig identities and Examples, Trigonometry

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In this video, Sal solves an interesting question from a college entrance exam in India that requires knowledge of arithmetic progressions, trigonometric identities, and algebra. He works through solving the problem step-by-step by...
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Instructional Video

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

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