Question 1067826
{{{a^2+a-4b^2-2b}}}
{{{a(a+1)-2b(2b+1)}}}
not helping.


Another way
{{{(a-2b)(a+2b)+a-2b}}}
{{{(a-2b)(a+2b)+(a-2b)}}}
{{{highlight((a-2b)(a+2b+1))}}}