Study Guide
Learning Objectives
- Apply the product property and connect $\log_b(kx)$ to a vertical shift (2.12.A.1).
- Apply the power property and connect $\log_b(x^k)$ to a vertical stretch (2.12.A.2).
- Use change of base; recognize logs as vertical dilations of each other (2.12.A.3).
- Identify $\ln x$ as $\log_e x$ (2.12.A.4).
- Expand and condense logarithmic expressions equivalently.
Suggested Practice Sequence
1. Expand $\log_b(xy)$ and $\log_b(x/y)$ (quotient via product + power). 2. Rewrite $\log_b(x^n)$ as $n\log_b x$. 3. Condense sums/differences back to single logs. 4. Change $\log_2 10$ to $\ln$ or $\log_{10}$. 5. Match $\log_b(3x)$ with $\log_b x+\log_b 3$ on a graph story.
Classroom / Check-In Moves
- Expand/condense card sort.
- Transformation matching: dilation vs translation.
- Calculator change-of-base demos.
Misconception Watch-List
- Distributing log over addition.
- $(\log x)^n$ vs $\log(x^n)$.
- Wrong change-of-base fraction orientation.
- Base of $\ln$ as 10.
Vocabulary to Own
- product property; power property; change of base
- expand; condense; equivalent form
- horizontal dilation; vertical translation; vertical dilation
- natural logarithm $\ln$; base $e$
Materials Map
- Practice: expand/condense and change base
- Word: rewrite models for interpretation
- Mixed / multi-*: link to 2.4 exp manipulation and 2.11 features
- Review & practice test: timed rewrite fluency
- Interactive: rule checks