The flight path of a surveillance drone in a vertical cross-section is modelled by the parametric equations
x=2t2−16t,y=t3−16t,t∈R x = 2t^2 - 16t, \quad y = t^3 - 16t, \quad t \in \mathbb{R} x=2t2−16t,y=t3−16t,t∈Rwhere x x\,x represents the horizontal displacement from a control tower and y y\,y represents the height relative to a safety baseline. The drone's path crosses the baseline at the origin and at the points A A\,A and BBB, where A A\,A and B B\,B are distinct points.
Find the coordinates of A A\,A and show that B B\,B has coordinates (96,0)(96, 0)(96,0).
Show that the equation of the tangent to the path at B B\,B is
x+y−96=0 x + y - 96 = 0 x+y−96=0The tangent to the path at B B\,B intersects the path again at the point PPP.
Find, using algebraic methods, the horizontal displacement of the drone at point PPP.
425 exam-style questions on OCR A Level Maths 1.7 Differentiation, covering 1.7.1 Derivative as gradient of the tangent, 1.7.2 Gradient of the tangent at a point, 1.7.3 Sketching the gradient function, 1.7.4 Second derivatives, 1.7.5 Second derivative as rate of change of gradient, 1.7.6 Convex, concave and points of inflection (A-level only), 1.7.7 Differentiation from first principles for powers of x, 1.7.8 Differentiation from first principles for sin x and cos x (A-level only), 1.7.9 Differentiating x^n, 1.7.10 Differentiating e^(kx) and a^(kx) (A-level only), 1.7.11 Differentiating trigonometric functions (A-level only), 1.7.12 Derivative of ln x (A-level only), 1.7.13 Tangents and normals, 1.7.14 Stationary points, 1.7.15 Increasing and decreasing functions, 1.7.16 Points of inflection (A-level only), 1.7.17 Product and quotient rules (A-level only), 1.7.18 Chain rule (A-level only), 1.7.19 Parametric and implicit differentiation (A-level only), 1.7.20 Constructing differential equations (A-level only), and 1.7 Differentiation. Each one has a worked solution and a mark scheme showing where the marks go.