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用指数函数建模（续）
当输入越来越大时，我们能对指数函数的行为说些什么？
1. Modeling temperature data
Modeling temperature data
2. Summary
Summary
3. Parent, scaled and shifted decays
How do p(t) = (0.95)^t, r(t) = 30(0.95)^t and F(t) = 42 + 30(0.95)^t relate?
4. Fridge and room temperatures
A cooling model F(t) = 42 + 30(0.95)^t describes a drink. What is the surrounding room temperature at t = 0, in degrees?
5. Average rates of a cooling model
A cooling model's average rates on [10,20], [20,30], [30,40] are -0.721, -0.432 and -0.258 degrees per minute. What do they show?
6. Building the potato model
A potato at 68 degrees approaches boiling at 212 degrees, following F(t) = a - b(0.98)^t. What are a and b?
7. A decaying exponential model has a horizontal asymptote
A function of the form a b^t + c approaches c as t grows without bound when 0 < b < 1.
8. Decaying shifted exponential value
A soda cooling in a 41-degree fridge follows F(t) = 41 + 31(0.95)^t from a 72-degree room. What is F(0), in degrees?
9. Average rate on successive cooling intervals
A cooling model has values 62.4 and 58.9 at t = 25 and t = 30. What is the average rate on [25, 30], to two decimals?
10. Reading a soda's cooling model
A soda's temperature F(t) = 72 - 31(0.95)^t is measured in a 72-degree room and cools after leaving the fridge. What are its fridge temperature and its long-run temperature?