Proof of the trig identity sin(a+b) = (cos a)(sin b) + (sin a)(cos b)
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Proof of the trig identity sin(a+b) = (cos a)(sin b) + (sin a)(cos b)
source
Good
Thanks it helped a lot
i watch a video that older than me
Marvel should’ve thrown away or rewrite the origin of 💩russian💩 characters.
It's been 16yrs
sorry too complicated for me but i understood t eh video anyways
Why do we need that line above BC?
In the same way, Sin m^n = ??? (Where m & n are real numbers, mustn't be an expansion, must be a FINITE SERIES.)
very neat way of explaining, as a tutor your this content is amazing
🙏
You have a mistakeeeee
Oh my god finally I understand haha
Everybody would have been Einstein if they thought about their life like this
i'm around 13 years late but this is cool! thanks 😀
This proof works quite nicely when the two angles sum to less than 90⁰, but for larger angles we can't use right triangles. In that case, how do we show the formula works for all angles?
Omg 13 years
Any one in todays date?
Mr. Sal Khan is soooo good!
How do you know angle AEB is a right angle?
Wonderful
But isn't this a proof only for this particular shape?????
This video is awesome, the way it's explained makes everything look pretty simple, great job !
This is not bad quality. This is lo-fi maths by Sal Khan.
Extending out to an additional right triangle and use of the inner angle definition— very clever