Question

A certain voltage can be expressed as v(t)=(5+t^2)u(t-1). What is the value of this voltage at t=3sec?

Answer 1

v(t)=(5+t^2)u(t-1)
and you are give t =3, just pulg in 3 where evr u see the't'
v(3)=(5+3^2)u(3-1)
= (5+9)u(2)
=28u

Answer 2

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