The curve C is defined implicitly by the equation exy+y=x2.
a. Derive an explicit formula for dxdy in terms of x and y. Present your work in a logically ordered sequence of steps.
b. Determine all points on C where the tangent line is horizontal. Express each point’s coordinates as ordered pairs and justify that your list is complete.
c. For x>0, decide whether the curve can possess a vertical tangent. Provide a mathematical argument that supports your conclusion.