Zadanie (x-2)+(3x+4)^2-(2x-1)(2x+1)
źródło:
(x-2)+(3x+4)^2-(2x-1)(2x+1)=
=x-2+9x^2+24x+16-(4x^2-1)=
=x-2+9x^2+24x+16-4x^2+1=5x^2+25x+15