1. Pierre de Fermat 1601 - 1665 Pierre de Fermat 1601 - 1665 Pierre de Fermat was a French lawyer and government official most remembered for his work in number theory; in particular for Fermat's Last Theorem. He is also important in the foundations of the calculus. Pierre de Fermat was a French lawyer and government official most remembered for his work in number theory; in particular for Fermat's Last Theorem. He is also important in the foundations of the calculus.

3. We can use implicit differentiation to find:

4. But so is positive. We can use implicit differentiation to find:

6. We could use the same technique to find and.

7. Example a. b. c. Example