1. ## Notation

Is finding the solution of;

$
(D^2+10D+25)y = 0
$

The same as solving;

$
y''+10y'+25y = 0
$

??

2. Originally Posted by AnnM
Is finding the solution of;

$
(D^2+10D+25)y = 0
$

The same as solving;

$
y''+10y'+25y = 0
$

??
Assuming by D you mean the differential operaor, yes.

RonL

3. If you mean a Difference Operator (non-continuous), then not quite.

4. Originally Posted by TKHunny
If you mean a Difference Operator (non-continuous), then not quite.
That is normaly uppercase delta $\Delta$, or upside down delta (nabla)
$\nabla$ for the forwards and backwards difference operators.

D is commonaly used for the differential operator.

RonL

5. Agreed.

I could not quickly find an example of D being used for a difference operator, at least not in the texts available to me. This surprises me. Maybe I dreamed up that I had seen it a time or two.

In any case, it is important to point out that notation is not always consistent. There is no substitute for the definitions provided in the discussion where the symbol is introduced.