(5)³-(2x-3)³= (5-2x+3)*(25+5(2x-3)+(2x-3)²)= (8-2x)*(25+10x-15+4x²-12x+9)= (8-2x)*(4x²-2x+19)= 2*(4-x)*(4x²-2x+19)
(5)³-(2x-3)³= (5-2x+3)*(25+5(2x-3)+(2x-3)²)= (8-2x)*(25+10x-15+4x²-12x+9)= (8-2x)*(4x²-2x+19)= 2*(4-x)*(4x²-2x+19)