Exponential Models Growth and Decay | 40 Worked Examples | Edexcel A-Level Maths

40 progressive Edexcel A-Level (9MA0) questions on exponential models of growth and decay, with full mark-scheme style worked solutions.

What’s inside:
Easy: interpreting A and k in y = A e^(kt), evaluating the model, initial values, long-term limits, and solving simple exponential equations.
Medium: rates of change by differentiating, half-life and doubling time, solving in worded contexts, cooling with an ambient offset, and linearising with logs (ln y against t).
Hard: finding two constants from data, two-point elimination, radioactive decay and drug half-life, Newton’s law of cooling, radiocarbon dating, and full multi-part modelling problems.

Contexts include population, cooling, radioactive decay, drug concentration and investment. Every solution shows every step, with M1 (method), A1 (accuracy) and B1 (independent) marks annotated at exactly the point each would be awarded, plus a plain-English note on every working line. Special care over the classic trap of isolating the exponential before taking logs. Typeset in LaTeX for clean mathematical notation.

Ideal for: Year 13 students sitting Edexcel A-Level Mathematics (9MA0) Paper 1 / Paper 2 Pure, plus tutors and teachers building targeted practice. Print-friendly, hand straight to students.