Here is another question that is from CJC H2 Mathematics 9758 Prelim Paper 1. Its a question on differentiation. I think it is simple enough and tests student on their thinking comprehension skills. This is question 6.

A straight line passes through the point with coordinates (4, 3) cuts the positive x-axis at point P and positive y-axis at point Q. It is given that , where and O is the origin.

(i) Show that equation of line PQ is given by .

(ii) By finding an expression for , show that as varies, the stationary value of is , where and are constants to be determined.