(adsbygoogle = window.adsbygoogle || []).push({}); Causal Function? (Electrical Engr)

1. The problem statement, all variables and given/known data

I have the following function:

d^2 y(t)/dt^2 + 3* dy(t)/dt + y(t) = dx(t)/dt +2x(t+1)

Where y(t) is the output and x(t) is the input.

I need to determine if it is causal or non causal.

2. Relevant equations

See above.

3. The attempt at a solution

My solution is that is causal since I can substitute t_1 = t+1 and t = t_1 -1, substituting this into the equation given:

d^2 y(t_1 -1)/dt^2 + 3* dy(t_1 -1)/dt + y(t_1 - 1) = dx(t_1 -1)/dt +2x(t_1)

And then if we say that t_1 = 0, I get:

d^2 y(-1)/dt^2 + 3* dy(-1)/dt + y(- 1) = dx(-1)/dt +2x(0)

And according to the definition, the equation does not depends on future inputs. Is my reasoning correct?

Thank You.

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# Homework Help: Casual Function? (Electrical Engr)

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