A specialist optical lens has a cross-section defined by the curve CCC. The coordinates (x,y)(x, y)(x,y), measured in millimeters, of the surface of the lens satisfy the equation
x2y+10y=2x3−15x2+k,y>0 x^2 y + 10y = 2x^3 - 15x^2 + k, \quad y > 0 x2y+10y=2x3−15x2+k,y>0where kkk is a constant.
Find dydx\dfrac{dy}{dx}dxdy in terms of xxx and yyy.
The point P(p,3)P(p, 3)P(p,3), where ppp is a constant, lies on CCC. Given that PPP is the minimum turning point on CCC,
find
(i) the value of ppp
(ii) the value of kkk
717 exam-style questions on Edexcel A Level Maths Differentiation, covering 9.1 Differentiating sin x and cos x, 9.2 Differentiating exponentials and logarithms, 9.3 The Chain Rule, 9.4 The Product Rule, 9.5 The Quotient Rule, 9.6 Differentiating Trigonometric Functions, 9.7 Parametric Differentiation, 9.8 Implicit Differentiation, 9.9 Using Second Derivatives, and 9.10 Rates of Change. Each one has a worked solution and a mark scheme showing where the marks go.