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CCSSAPhigh school

AP Precalculus -- Exponential and Logarithmic Functions

Master exponential and logarithmic functions for the AP Precalculus exam. You will connect sequences to functions, model real-world growth and decay, wield logarithm properties to solve equations, and use semi-log plots to validate your models -- all skills tested in Units 2-3.

5units
8topics
139questions
~3hours

Course Units

Learning objectives

  • Write explicit and recursive formulas for arithmetic sequences and identify the common difference
  • Write explicit and recursive formulas for geometric sequences and identify the common ratio
  • Distinguish arithmetic (additive) from geometric (multiplicative) patterns in tables and contexts
  • Connect arithmetic sequences to linear functions and geometric sequences to exponential functions
  • Determine the nth term of a sequence from a real-world context

Learning objectives

  • Identify exponential growth (b > 1) and decay (0 < b < 1) from equations and graphs
  • Apply transformations (shifts, reflections, stretches) to exponential functions and describe their effects
  • Model real-world phenomena with exponential functions (population, radioactive decay, compound interest)
  • Determine the growth/decay rate and initial value from a function or data set
  • Convert between different exponential forms including base-e and arbitrary-base representations

Learning objectives

  • Convert between exponential and logarithmic forms fluently
  • Apply properties of logarithms (product, quotient, power rules) to expand and condense expressions
  • Graph logarithmic functions and identify domain, range, vertical asymptote, and key points
  • Recognize logarithms as inverses of exponential functions and use this to solve problems
  • Evaluate logarithms of any base using the change-of-base formula

Learning objectives

  • Solve exponential equations by taking logarithms of both sides and isolating the variable
  • Solve logarithmic equations by converting to exponential form
  • Identify and check for extraneous solutions that arise from domain restrictions
  • Apply these techniques to real-world problems (half-life, doubling time, pH, decibels)
  • Solve equations involving multiple exponential or logarithmic terms

Learning objectives

  • Interpret semi-log plots and explain why exponential data appears linear on them
  • Use residual analysis to evaluate how well a model fits the data
  • Compare linear, exponential, and polynomial models for a given dataset and justify your choice
  • Transform data using logarithms to achieve linearity and extract model parameters
  • Identify when a dataset does not follow an exponential trend from semi-log plot curvature