Does it cancel out?

[@r3birth]

nice vid! easier way for me: theta = arccosx -> cos(theta) = x/1. build right triangle. sin(theta) = sqrt(1-x^2)

[@aryaaskmaths]

Thank you. Yes using the triangle is another perfectly valid method (it's actually the same idea since the sin^2x + cos^2x = 1 identity is derived from Pythagoras).