Waivio

Recommended Posts

Trigonometry Identities: cos(x +/- y) = cos(x)cos(y) -/+ sin(x)sin(y)

3 comments

mes4.3 K2 years agoPeakD2 min read

In this video I derive addition and subtraction identities, cos(x+y) and cos(x-y), using the Law of Cosines and the Pythagorean Theorem. This identity is very useful in all of mathematics and is used in the derivations of many trigonometric derivatives and integrals.

Download video notes: https://1drv.ms/b/s!As32ynv0LoaIid8UuG5DAPd9tNe_-A?e=TG9QGg


Watch video on:


View Video Notes Below!


Download these notes: Link is in video description.
View these notes as an article: https://peakd.com/@mes
Subscribe via email: https://mes.fm/subscribe
Donate! :) https://mes.fm/donate
Buy MES merchandise! https://mes.fm/store
More links: https://linktr.ee/matheasy
Follow my research in real-time on my MES Links Telegram: https://t.me/meslinks
Subscribe to MES Truth: https://mes.fm/truth

Reuse of my videos:

  • Feel free to make use of / re-upload / monetize my videos as long as you provide a link to the original video.

Fight back against censorship:

  • Bookmark sites/channels/accounts and check periodically
  • Remember to always archive website pages in case they get deleted/changed.

Recommended Books:

Join my forums!

Follow along my epic video series:


NOTE #1: If you don't have time to watch this whole video:

Browser extension recommendations:


Trigonometry Identities

https://files.peakd.com/file/peakd-hive/mes/245cqBerFa48h2aKeJagXvc1NNwkk5hQKkciNWxA1zKCs5p1wGdUGrKKx3nPpbsHDB49d.jpg

Cosine Addition and Subtraction Formulas

Subtraction: cos(x-y) = cos(x)cos(y) + sin(x)sin(y)

https://files.peakd.com/file/peakd-hive/mes/Eo4JhGpWhq8eo7sAucMfD5WCo3U579sJqPJZgdXcwsknbShLCB4A7kZPu5TcpX1A2fH.png

https://files.peakd.com/file/peakd-hive/mes/Eo2BJ5b2bdT5Jib29a6vctcLZZXDNiniqbvx7o7rJdq6CxvE2BfgCyGkTYBVFFUYX6K.png

https://files.peakd.com/file/peakd-hive/mes/23tHbkj8B2891AXqKbyf19xBbzDQ1Vohy2WgRe7jtJnJaqSNXAFqP349oY4wZMRD1kEYY.png

Addition: cos(x+y) = cos(x)cos(y) - sin(x)sin(y)

https://files.peakd.com/file/peakd-hive/mes/23tSym8QDYFCrN6YGqxiMnVAi46H3pxVMMWiHtMTdHQZ74cmrGsu77SJS5Ge2E1iDWXog.png

Combining Addition and Subtraction Formulas

https://files.peakd.com/file/peakd-hive/mes/EoH56SDQx11ivDeJqLzPjZVTMj6DbfH3YHiPsGFK6Gr4xUFMS2zuGhUSAHWgfaEw3Q4.png

Comments

Sort byBest
AI
Waivio AI Assistant
How can I help you today?