This is he proof to d/dx arcsin.
Everything makes perfect sense up to when arccos = (1-sin(y)^2)^1/2
I understand that those numbers in the identity of arccos using Pythagoras a^2+b^2=c^2 -> sin^2+cos^2 = 1^2
Thant makes sense.
My questions is why do we use the identity?
Why don’t we just use 1/(arccos) as the answer?
What’s with the extra step turning 1/(arccos) into 1/(1-arcsin^2)^1/2?