(a) The curve with equation yo = x' + 3xis called the Tschirnhausen cubic. Find an equation of the tangent line to this curve at the point (1, 2). (b) At what points does this curve have a horizontal tangent? (x, v) = ( (smaller y-value) (x, y) = (larger y-value) (c) Illustrate parts (a) and (b) by graphing the curve and the tangent lines on a common screen. O 2 -3 O