Is exponentials and logarithms on the AQA, Edexcel and OCR A Level Maths exams?
Yes. Exponentials and Logarithms is part of the A Level Maths content that every board examines: AQA section F, Edexcel Pure 6, OCR 1.06. It is assessed in AQA Paper 1, and Section A of Papers 2 and 3; Edexcel Paper 1 and Paper 2; OCR A Paper 1, and the pure sections of Papers 2 and 3.
Is exponentials and logarithms Year 12 or Year 13 content?
Both. The AS content, usually taught in Year 12, is: Exponential functions y = aˣ and y = eˣ, and their graphs; Logarithms, the laws of logarithms and ln x as the inverse of eˣ; Solving equations of the form aˣ = b; Exponential growth and decay models and their limitations; Using logarithmic graphs to estimate parameters in y = axⁿ and y = kbˣ. The full A Level adds: Differentiating and integrating eˣ and ln x (see the calculus pages).
How do I turn y = kbˣ into a straight line?
Take logarithms of both sides: log y = log k + x log b. Plotting log y against x gives a straight line with gradient log b and intercept log k.