Question 164339
{{{2x^4-x^3+2x-1}}}
={{{2x^4+2x-x^3-1}}}
={{{(2x^4+2x)-(x^3+1)}}}
={{{2x(x^3+1)-(x^3+1)}}}
={{{(x^3+1)(2x-1)}}}
={{{(x+1)(x^2-x+1)(2x-1)}}}