A curve has the equation \(y = x^3 - 5x^2 + 7x\).
- Show that the curve only crosses the \(x\)-axis at one point. [4]
The point \(P\) on the curve has coordinates \((3, 3)\).
- Find an equation for the normal to the curve at \(P\), giving your answer in the form \(ax + by = c\), where \(a\), \(b\) and \(c\) are integers. [6]
The normal to the curve at \(P\) meets the coordinate axes at \(Q\) and \(R\).
- Show that triangle \(OQR\), where \(O\) is the origin, has area \(28\frac{1}{8}\). [3]