tan(x/x0) = y/A
=> x/x0 = tan-1(y/A)
Diff wrt time.
Vxx0 = 11 + y²A² * VyA
=> Vxx0 = AA² + y² * Vy
Now Vy = A sec²(xx0) * Vx/x0
tan(x/x0) = y/A
=> x/x0 = tan-1(y/A)
Diff wrt time.
Vxx0 = 11 + y²A² * VyA
=> Vxx0 = AA² + y² * Vy
Now Vy = A sec²(xx0) * Vx/x0