Exponentials and Logarithms

What happens when the variable moves into the index — and the tool that brings it back down.

• An Overview — the big idea, the laws, and the common mistakes

The specification statements

• EL1 · Exponential Functions — the function kaˣ and its graph, for positive a
• EL2–EL3 · Logarithms and Their Laws — the logarithm as the inverse of raising to a power, and the three laws
• EL6 · Solving Exponential Equations — equations with the unknown in the index, and disguised quadratics
• EL4–EL5 · Reduction to Linear Form — turning exponential and power models into straight lines
• EL7 · Growth and Decay — compound interest, populations, half-life and cooling

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Each page has step-by-step notes, several worked examples, a quick-reference grid and ten practice questions with fully worked solutions.