Question 200673
{{{3x^3-12x}}}
={{{3x^3-3*4x}}}
={{{3x*x^2-3x*4}}}
={{{3x(x^2-4)}}}  factor 3x out as it is the common factor of both terms
={{{3x(x^2-2^2)}}}  x^2-2^2 can be factored further
={{{3x(x+2)(x-2)}}}