\includegraphics{figure_6}
The diagram shows the curve with parametric equations
$$x = 1 + \sqrt{t}, \quad y = (\ln t + 2)(\ln t - 3),$$
for \(0 < t < 25\). The curve crosses the \(x\)-axis at the points \(A\) and \(B\) and has a minimum point \(M\).
- Show that \(\frac{\mathrm{d}y}{\mathrm{d}x} = \frac{4\ln t - 2}{\sqrt{t}}\). [4]
- Find the exact gradient of the curve at \(B\). [2]
- Find the exact coordinates of \(M\). [3]