(a) Lineárne
y(t) = k.x(t)
(b) Princíp superpozície
x(t) -> y(t)
x(t) = x1(t) + x2(t)
x1(t) -> y1(t)
x2(t) -> y2(t)
x(t) -> x1(t) + x2(t) => y(t) = y1(t) + y2(t)
x(t) = a.x1(t)
y(t) = a.y1(t)
(c) Časovo invariantné
x(t) -> y(t) x(t-t0) -> y(t-t0)