Standard +0.3 This is a straightforward application of the quotient rule followed by solving a simple equation. Students must differentiate the rational function, set dy/dx = -4, and solve for x-coordinates. While it requires multiple steps (differentiation, equation setup, algebraic manipulation), each step is routine and the question follows a standard template with no conceptual surprises.
2 A curve has equation
$$y = \frac { 3 x + 1 } { x - 5 }$$
Find the coordinates of the points on the curve at which the gradient is - 4 .\\
\hfill \mbox{\textit{CAIE P2 Q2 [5]}}