An environmental study models the concentration of a pollutant, PPP, in a stream as P=ln(0.8t)P = \ln(0.8t)P=ln(0.8t), where t>0t > 0t>0 is the time in hours after a treatment process begins. Determine the exact value of the rate of change of the concentration with respect to time at the instant when t=2.5t = 2.5t=2.5.
Practise AQA A Level Maths 1.10 G: Differentiation with exam-style questions for A Level Maths. 321 questions covering 1.10.1 The derivative and second derivative, 1.10.2 Differentiating standard functions, 1.10.3 Applications of differentiation, 1.10.4 Product, quotient and chain rules (A-level only), 1.10.5 Implicit and parametric differentiation (A-level only), and 1.10.6 Constructing differential equations (A-level only), matched to the AQA A Level Maths (7357) specification and written in Paper 1, Paper 2 and Paper 3 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.
