() For any smooth curve in the first quadrant, and any point (0, 0) on the curve, define two right triangles: the basic triangle, with vertices at (o, yo), (0, 0), and (0, 0), and the tangent triangle, with vertices at (o, yo), (0, 0), and the x-intercept of the tangent line to the curve. Find a smooth function f(x) for which the curve y = f(x) passes through the point (2, 4) and has the following property: at any point (x, y) on the graph with a > 0, the the area of the tangent triangle is 9 times the area of basic triangle. ANSWER: f(x) =