Sum and Difference Formulas

How to use the Sum and Difference Formulas to find the exact value of the sine, cosine or tangent of an angle.

0:12 Formulas for sine, cosine and tangent sum and difference formulas
1:09 Example 1 Finding 7pi/12 using the sine sum formula
3:31 Example 2 looks at condensing a cosine sum expression
4:37 Example 3 looks at working with the tangent difference formula

Related Videos:

Double Angle Formulas:

Half Angle Formulas:

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[meganterry]

SO helpful and the video isn’t unnecessarily long. Straight, to the point, and explained in a clear understandable way. MUCH appreciation to you!

[nickymujica]

thank you so much for this channel. Your videos are amazing and they’re very short but you do such a great job explaining things.

[jasonmcclendon]

I use your videos in stead of the ones provided by my math classes and they help me understand the concepts much faster.

[lesliepalmer]

Your method of converting to degrees makes so much sense and saves so much work. This is incomparable to my online professor's attempt at video for this lesson. Thank you for all you do, Saint Mario!

[apothe]

This might be the best video explaining how to find exact values using the sum and difference formula. Thank you Mario. It's super helpful and covers every detail.

[erynvonhusen]

Your videos are appreciated! I know I can watch your videos and understand within 10 minutes! Thank you.

[katiepotter]

Awesome job. Very concise explanations with great examples. Hope you keep on making videos! :)

[yettispaghetti]

Thanks for the help, I would've probably been stuck staring at my homework problems for hours without this video!

[alexiayeraldin]

Hello Mario, on your last example problem using tangent. For the sine of u which was -5/12 you just put 5/12. You corrected the cosv but not the sinv. I just wanted to point that out. Great video!

[MrRyanrichardson]

Praise be to you Mario, you are on your way to sainthood. thanks for the help

[spiderthatjumps]

this is the mercy the universe provides when I fall asleep in math

[elysiaramsey]

so if the original is an addition will the right side sign be addition as well or is it flipped?

[emilyvinet]

you should've worked out the tan problem :(