Question

- L - - - - - -2 t (s) Entire an equivalent function for the plot shown here using the step function, u(t)

please answer this in matlab so it can match the function. thank you

Answer 1

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          Please find the answer attached as under. Please give a thumbs up rating if you find the answer useful! Have a rocking day ahead!

The sine wave can be repreented by the following equation : y(t) = sin(2*pi*0.25*(t-0.5)). However, the sine wave is clipped on the time axis, on either side. This is where the step function comes in. The clipped step function can be represented as x(t) = u(t+3.5) - u(t-0.5). Thus, the function becomes:

f(t) = x(t)y(t) = sin(2*pi*0.25*(t-0.5))*[u(t+3.5) - u(t-0.5)]

This is plotted in Matlab as follows:

t = -5:0.01:5;
x = double(t>=-3.5) - double(t>=0.5); % the unit step function
y = sin(2*pi*0.25*(t-0.5)); % sine function
f = x.*y;
plot(t,f,'LineWidth',2);
grid;
xlabel('Time(s)');
ylabel('Magnitude');

Output:

Magnitude -5 4 -3 -2 -1 1 2 3 4 5 0 Time(s)

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