this instructions may be helpful in solving the problem:The CONV commandConv(x, h) returns the convolution sum of the vectors x and h. When using this command, one must compensate for the fact that MATLAB only allows vectors to be indexed from 1. When the input vectors have values for n < 1 (i.e. x[0], x[-1], etc.), you must keep track of the vector index that you associate with the value at x[0] (call this the zero'th position of vector x). When computing the convolution sum of two vectors, the zero'th position in the output vector (i.e. the position in the output vector that corresponds to y[0]) can be found using the following equation:zy = zx + zh - 1where zy is the position of the output vector, and zx and zh are the zero'th position of the input vectors. Consider the following example:x[n] = [0, 0, 1, 3, 2, 3, 1, 0, 0] h[n] = [0, 0, 0, 1, 1, 2, 2, 0, 0, 0]where the bold font marks the zero'th position (i.e. x[0] = 3, h[0] = 0). The following MATLAB program defines x and h, and computes y = x * h.>> x = [0 0 1 3 2 3 1 0 0]; >> h = [0 0 0 1 1 2 2 0 0 0]; >> y = conv(x, h);The zero'th index of vector x is 4 since x[4] corresponds to the value of vector x at n = 0. Likewise, the zero'th index of vector h is 1 since h[1] corresponds to the value of vector h at n = 0. The zero'th position of the output vector y is calculated to be 4 in this case.Adjusting your plots to display the correct x axisTo plot y with the time axis correctly adjusted, one shifts the x axis to the right by four (i.e. subtracting 4 from the values in the x axis). This can be done by supplying an additional parameter to the 'stem' or 'plot' command:>> stem (-3:(length(y)-4), y); {plots y with the time axis correctly compensated}Note that -3:(length(y)-4) was determined by subtracting 4 from the value of the first index of y (i.e. 1 - 4 = 3) and from the value of the last index of y (i.e. length(y) - 4). Note also that stem and plot both require that the given range is the same 'size' as the vector to be plotted (i.e. size(-3:(length(y)-4)) = size(y)). Adjustments like the one made above are common in MATLAB since all vectors are indexed starting from 1, so you should pay attention to the x axis every time you make a plot.