Exponential and logarithmic functions
Index laws, fractional indices, logarithms and the log laws, solving exponential and log equations, graphs of y = a^x and y = log_a x, and growth and decay applications.
Sections
- 9A Indices Powers, the index laws for products, quotients and powers, and the meaning of zero and negative indices.
- 9B Fractional indices The meaning of a^(1/n) and a^(m/n) as roots, converting between surds and indices, and why the base must be positive.
- 9C Logarithms The definition of a logarithm, finding logs by writing numbers as powers, logs of fractions and roots, the calculator, and locating a log between two integers.
- 9D The laws for logarithms Logs and exponentials as inverse functions, the three log laws, and the particular values log_a 1, log_a a and log_a (1/x).
- 9E Equations involving logarithms and indices The change-of-base formula, solving index equations by matching bases or taking logs, equations that reduce to quadratics, log equations, and exponential inequations.
- 9F Exponential and logarithmic graphs The graphs of y = a^x and y = log_a x, their asymptotes and key points, and how reflections, translations and dilations change them.
- 9G Applications of exponential and log functions Exponential growth and decay models, doubling time and half-life, rearranging formulas between index and log form, and log scales such as pH.
Coaching Centre