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CasualDays
Sep1-08, 06:37 PM
1. The problem statement, all variables and given/known data
Let \theta(x) be the step function:

\theta(x) be equivalent to

1, if x > 0
0, if x \leq 0

Show that \frac{d \theta }{dx} = \delta(x)


2. Relevant equations
In the previous portion I was able to prove
x \frac{d}{dx} (\delta(x))= -\delta(x)


3. The attempt at a solution
I thought the problem was a heavyside problem but upon closer inspection, I noticed that on the heavyside step function it is 1 when x \geq 0.

So how do I resolve this? Is there a way to change it so that it looks like a heavyside function, because that makes the problem much more convenient.:rofl:

tiny-tim
Sep2-08, 05:22 AM
Hi CasualDays! :smile:

(have a theta: θ and a delta: δ :smile:)

Hint: what is 1 - θ(x)? :wink:

CasualDays
Sep2-08, 11:15 AM
Hi CasualDays! :smile:

(have a theta: θ and a delta: δ :smile:)

Hint: what is 1 - θ(x)? :wink:

It's always the easy solutions that allude me..:biggrin: