Question

proof that cos(inverse sinx) = squareroot(1-x^2 )

Answer 1

Call theta = sin^-1 (x). sin (theta) = x.
In a right triangle, the opposite side a = x, hypotenuse c = 1, thus b = sqrt (1 - x^2).
Accordingly, cos (theta) = b/c = sqrt (1 - x^2)

Answer 2

Thank you