Start with
Differentiate both sides.
Quotient rule. Etc.
(p.s. If x and y are changing, then the hypotenuse is NOT constant!)
basically I don't understand the suggestion on how this was set up
Let (in radians) be an angle in a right triangle, and let x and y, respectively, be the lengths of the sides adjacent to and opposite Suppose that x and y vary with time.
(a) How are , and Related
the book says that
thanks for help
actually I don't know where the comes from I assume the hypotenuse is a constant