Final answer:
To find x[n], we need to identify the samples of x(t) at regular intervals of 1 msec.
Step-by-step explanation:
When a continuous-time function is sampled every 1 msec, it becomes a discrete-time function. This means that the function is only defined at specific points in time. To find x[n], we need to identify the samples of x(t) at regular intervals of 1 msec. For example, if x(t) is given by x(t) = 2t, then x[0] = 2(0) = 0, x[1] = 2(0.001) = 0.002, x[2] = 2(0.002) = 0.004, and so on. These sampled values constitute the discrete-time function x[n]