Exponentials and logarithms
Laws of logarithms
What a logarithm is (the power you need), the three laws that come straight from the index laws, and how to combine and simplify logarithms, including and .
≈ 40 minThe functions eˣ and ln x
Meet , the most natural base for growth, and its inverse : their graphs, asymptotes and intercepts, transformations, inverses and exact answers.
≈ 40 minExponential equations and inequalities
Bringing an unknown power down with logarithms: solving , equations with in two powers, disguised quadratics, and inequalities like "the smallest such that ".
≈ 40 minLogarithmic equations
Solving equations with the unknown inside a logarithm: combine with the log laws, remove the logs by raising to a power, and always check that the answers are in the domain.
≈ 35 minExponential models and linear forms
Using logarithms in the real world: modelling growth and decay with , and turning curves like and into straight lines so their constants can be read from a graph.
≈ 45 min