The profile of a suspended track for a high-speed transport system is modelled by the curve CCC. The path of the track starts at point P P\,P and ends at point QQQ, as defined by the parametric equations
x=12t2+2t+10 x = \frac{1}{2}t^2 + \frac{2}{t} + 10 x=21t2+t2+10 h=3t+12t h = 3t + \frac{12}{t} h=3t+t12where 1≤t≤61 \le t \le 61≤t≤6.
The horizontal distance from a sensor at the origin is x x\,x metres, and h h\,h is the height of the track above the ground in metres.
P P\,P is the point on the track where t=1t = 1t=1 and Q Q\,Q is the point where t=6t = 6t=6.
Safety regulations require that the difference in height between the start point P P\,P and the end point Q Q\,Q must be less than 6 metres. Show that the track meets this requirement.
Find an expression for dhdx\displaystyle \frac{dh}{dx}dxdh in terms of ttt.
A vertical reinforcement pillar is placed between the ground and the lowest point R R\,R on the track. Find the height of this pillar.
Calculate the acute angle the track makes with the horizontal at the end point QQQ. Give your answer to the nearest degree.
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.