Homework Help: Simple Derivitive

1. Jan 6, 2007

Dr Game

It's been a while, but how would you go about deriving

$$y = C e^-^5^x$$

and plug it into this equation

$$y'' + 4y' - 5y = 0$$

i can do this without C the answer would be 0, but what do I do with C there?

2. Jan 6, 2007

cristo

Staff Emeritus
You just differentiate it as usual, leaving the C in front of the terms, and then plug the first and second derivatives into the equation.

3. Jan 6, 2007

Dr Game

alright thought so, so I should get the same answer if C wasn't there, which is 0

$$25Ce^-^5^x+4(-5Ce^-^5^x)-5Ce^-^5^x = 0$$

4. Jan 6, 2007

cristo

Staff Emeritus
Yes, that's correct