1.

x(t) = 1I(t) -0x01 graphic
* t *1I(t) + 0x01 graphic
* (t - 0x01 graphic
) * 1I(t - 0x01 graphic
) - 0x01 graphic
* (t - t0) * 1I(t - t0) - 1I(t - t0)

2.

x(t) = 0x01 graphic

3.

x(t)= 0x01 graphic