Find the convolution of x(n) and h(n). where where the convolution is note the symbol is not multiply, it is the convolution operator. Also y(n) is causal, which means y(n) is only defined for , where n=0,1,2,3.... Now, Plugging in, Simplifying, The argument passed into the unit step must be or else the value of the unit step function is 0. So if I need to change my limits of summation so that the two unit step functions resolve to 1. That is, if then . if then . So the limits on k would be, if if I am bamboozled by the two lower limits on k. How can I do a summation with two lower limits? Would the summation diverge?