All questions of Sampling Theorem for Electrical Engineering (EE) Exam

The value of d(t-34)*x(t 56) can be found by evaluating the product of the delta function d(t-34) and the function x(t 56).

Since the delta function d(t-34) is non-zero at t=34 and zero everywhere else, we can substitute t=34 into the function x(t 56) to find the value of the product:

d(t-34)*x(t 56) = d(34-34)*x(34 56)

Since 34-34 = 0, the delta function becomes d(0) which is equal to 1:

d(t-34)*x(t 56) = 1*x(34 56)

Now, we need to evaluate the function x(t 56) at t=34:

x(34 56) = x(90)

The value of x(90) will depend on the specific function x(t), which is not provided in the question. Therefore, we cannot determine the exact value of d(t-34)*x(t 56) without knowing the function x(t).

So, the answer is indeterminate without additional information.

The impulse response of a system is the output of the system when an impulse input is applied to it. In this case, we have three systems (h1, h2, and h3) cascaded together, and we need to find the overall impulse response.


When multiple systems are cascaded together, the output of one system is connected to the input of the next system. Mathematically, the overall impulse response (H) can be found by multiplying the individual impulse responses (h1, h2, h3) together.


We are given the following impulse responses:
- h1 = u(t) (unit step function)
- h2 = exp(t) (exponential function)
- h3 = sin(t) (sine function)


To find the overall impulse response, we multiply the individual impulse responses together:

H = h1 * h2 * h3

Substituting the given values:

H = u(t) * exp(t) * sin(t)

Therefore, the correct answer is option 'A': sin(t) * exp(t) * u(t).


In cascaded systems, the overall impulse response is obtained by multiplying the individual impulse responses together. In this case, the overall impulse response is sin(t) * exp(t) * u(t).