Kontrollküsimused 3. osa kohta – Signaalitöötluse põhivara

Which signal is shown on the figure?

2*sin(2*t+Pi/2)

2*cos(t+Pi/2)

2*cos(t-Pi/2)

sin(2*t-Pi/2)

cos(2*t-Pi/2)

According to Euler formula equals to ...

Which of the following signals are periodic?

A discrete time signal is shown on the figure below. What is the formula of the signal?

u[n-2]-u[n+4]

u[4]-u[2]

u[2-n]-u[n-4]

u[n+2]-u[n-4]

Is the sum of two periodic signals also always periodic?

False

True

Consider these signals:

1.

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2.

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3.

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4.

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5.

Match the equations with the corresponding signals!

Signal #1	u[n+2] Unselect delta[n-3] Unselect e^wt Unselect e^jwt Unselect cos(t) Unselect
Signal #2	u[n+2] Unselect delta[n-3] Unselect e^wt Unselect e^jwt Unselect cos(t) Unselect
Signal #3	u[n+2] Unselect delta[n-3] Unselect e^wt Unselect e^jwt Unselect cos(t) Unselect
Signal #4	u[n+2] Unselect delta[n-3] Unselect e^wt Unselect e^jwt Unselect cos(t) Unselect
Signal #5	u[n+2] Unselect delta[n-3] Unselect e^wt Unselect e^jwt Unselect cos(t) Unselect

A system is described with y(t)=x(t)*cos(w*t), where x(t) is the input of the system. Is the system linear?

True

False