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对数函数的性质与应用（续）
对数遵循哪些与指数法则类似的结构规则？
1. Putting logarithms to work
Putting logarithms to work
2. Summary
Summary
3. Bacteria population model
A population with P(0) = 2.475 and P(10) = 4.298 follows P(t) = A e^(kt). What is A?
4. Solving for a rate constant
Solve 41 = 50 e^(-7k). What is k, to four decimal places?
5. Solving a shifted exponential for k
Solve 7 e^(2k-1) + 4 = 32. What is k, to four decimal places?
6. A log can be rewritten in any base
A logarithm in one base can be converted to another base by dividing by the logarithm of the new base.
7. Logistic doubling and half-life reasoning
Two populations each grow exponentially; one doubles every 3 years and another every 7. Which has the larger rate constant k in P(t) = A e^(kt)?
8. Doubling time from two measurements
A population measured at 250 at t = 4 and 500 at t = 11 follows P(t) = A e^(kt). What is its doubling time?
9. A population doubling in three years grows by a fixed amount yearly
If a population doubles every three years, it gains the same number of members each year.