can anyone help me ?
i have a homework and i did't find any answer for it
the question is
find the Domain , Range , matrix and the digraph for the relation R
a ) A = { 1,2,3,4,8 } = B , aRb if and only if a=b
b) A = { 1,2,3,4,6 } =B , aRb if and only if a multiple of b