Presuming you already have your math worked out...
as you cycle through each "times" (x1, x2, x3, ...), you set the innerHTML of each table cell to the value.
if "i" is the counter in your loop and "num" is what you are multiplying by, and each cell in your table has an id such as "ans1", "ans2", etc.:
ans = num * i
document.getElementById('ans' + i).innerHTML = ans