Question 970922

{{{(x-4)/(x^3-64)}}}


{{{(x-4)/(x^3-4^3)}}}


{{{(x-4)/((x-4)(x^2+4x+16))}}}


{{{cross((x-4))1/(cross((x-4))(x^2+4x+16))}}}


{{{1/(x^2+4x+16)}}}