## Goten77 find the derivative below one year ago one year ago

1. Goten77

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2. Goten77

$e ^{x}e ^{y}= \pi$

3. hba

wrt ?

4. hartnn

use either product rule, or $$e^x=\pi e^{-y}$$ then differentiate. if not mentioned, its always w.r.t x.

5. hartnn

even better $$e^{x+y}= \pi \\ x+y =\ln \pi \\ now \:\:differentiate.$$

6. Goten77

i was going to use the product rule but using log propertys makes it easier....

7. hartnn

yup, so dy/dx is just -1