## Saturday, December 19, 2009

### Zombie Dogs Attack!

An extra credit assignment for my calculus class:
A pack of zombie dogs (ZDs) is reproducing quickly and killing humans. Scientists and calculus students have determined that the the total number of human deaths due to ZDs t days after the start of 2010 is given by

1. At the end of January 1st (t = 1), how many deaths have occurred?

2. At the end of January, how many deaths will have occurred?

3. Determine the number of deaths/day after t days: hâ€²(t).
Hint: you may want to go â€œoutside-inâ€ with the chain rule.

4. Graph both h(t) and h'(t) on the same axes:

5. On what day will 90% of the human population (6.8 billion) be annihilated by ZDs?

6. When does the death rate reach half a billion per day?

7. When does the death rate hit its peak?

## Sunday, December 6, 2009

### Nonlinear graph shapes

I collected a set of various nonlinear graphs and hid the labels and scales.Â  They're good for discussions (I'm teaching exponential growth now).Â  Here's the Word file.

Can you match them all? Height of a projectile, iTunes sales, World Population of gorillas, Transfer speed versus message size on several networks, Heights of a group of men, Population of fruit flies in a container, Decay of radioactive atoms, Heights of babies over time.