Is x(t) equal to the shifted step function u(t+2)-u(t)?

Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
1 reply · 2K views
Drao92
Messages
70
Reaction score
0

Attachments

  • Stepf.png
    Stepf.png
    1.1 KB · Views: 710
Physics news on Phys.org
The basic definition is
[tex]u(t) = \begin{cases} 0 & t < 0 \\ 1 & t > 0 \end{cases}[/tex]
(and usually it's defined as u(0) = 1/2, but let's ignore that for now).

So the shifted step function is 1 only if t - a > 0, which means if t > a.

From your graph I gather that you want a function which is 1 if -2 < x < 0 and 0 otherwise. You can easily verify your answer x(t) = u(t + 2) - u(t) by considering the regions x < -2, -2 < x < 0 and x > 0 separately.
E.g. what do x(-3), x(-1) and x(1) work out to?