Results 1 to 3 of 3

- April 22nd 2009, 04:03 AM #1

- Joined
- Feb 2009
- Posts
- 17

## Help please

If I have the second order differential equation

y'' + y = 0

The auxilliary equation is

m^2 + m = 0

The two solutions are therefore

m = 0, -1

so

y = A*exp(0*x) + B*exp(-1*x)

Is this correct?

My notes say the solution is

y = C1*cos(x) + C2*sin(x)

can anyone explain please

- April 22nd 2009, 04:45 AM #2

- April 22nd 2009, 05:02 AM #3

- Joined
- Feb 2009
- Posts
- 17