The derivative of arcsin(x/a)\arcsin(x/a)arcsin(x/a) is:
1/a2−x21 / \sqrt{a^2-x^2}1/a2−x2
a/a2−x2a / \sqrt{a^2-x^2}a/a2−x2
1/(a1−(x/a)2)1 / (a\sqrt{1-(x/a)^2})1/(a1−(x/a)2)
Both a and c