Use "first derivative" in a sentence

1. the cost of bankruptcy, and the first derivative of the entire function will equal zero,

2. that maximizes when the first derivative is equal to zero

3. when the first derivative equals zero

4. point where the first derivative of the function is equal to zero and is the prime

5. And this is really interesting, because the gamma of an option is the first derivative of the delta

6. The first derivative product developed to be based on a volatility oriented index was the VIX futures contract