Determine whether the given relation is an implicit solution to the given differential equation. Assume that the relationship does define y implicitly as a function of x and use implicit differentiation.
y - ln y = x^2 + 1, dy/dx = 2xy/y - 1
x^2 + y^2 = 4, dy/dx = x/y
e^xy + y = x - 1, dy/dx = e^-xy - y/e^-xy + x