What is the linear convolution between x(n) and v(2n)
So far my professor was doing the convolution only with the tabular method and I don't know how to do this using delta functions
What is the linear convolution between x(n) and v(2n)
So far my professor was doing the convolution only with the tabular method and I don't know how to do this using delta functions
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We want the convolution of $\delta(x+1)+2\delta(x)+\delta(x-1)$ with $\delta(x+2)+\delta(x-2)$. Since these respectively integrate to $4,\,2$, the problem is equivalent to determining the distribution of $X+Y$ in terms of Dirac spikes, with independent $X,\,Y$ where$$P(X=1)=P(X=-1)=\tfrac14,\,P(X=0)=P(Y=2)=P(Y=-2)=\tfrac12,$$then multiplying all weights by $8$. So now you don't even need calculus. You're welcome to determine the full result from first principles, but for a multiple choice question we have a shortcut. All weights must be $\ge0$ (this is an advantage of recasting the problem into probabilities), which eliminates B, C and D, and $X+Y=-3$ is achievable, which eliminates E, so A is right.