Module 4 – Exponential and Logarithmic Functions

Section 4.3 – Logarithms and Logarithmic Functions

If a site is contaminated with a radioactive material of half life one week so that the level of radiation is now ten times the safe level, how long will it be before it is safe?

This amounts to solving for the time t in an exponential equation. It is possible to get a rough answer by trial and error, but the ideas of this section provide a better way.

What to do

  1. Use the Reading Guide to guide your reading of section 4.3 of the text. Read the following Study Notes and Discussion, and make sure that you have absorbed the main points by answering the questions.
  2. Follow the instructions regarding Further Practice until satisfied that you have met the Learning Objectives for this section.
  3. Then proceed to the next one.

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