(x^2+4x+3)(x^2+6x+8)-48=(X+1)(x+3)(x+2)(x+4)-48=(X+1)(x+4)(x+3)(x+2)-48=(X^2+5X+4)(x^2+5x+6)-48=(x^2+5x)^2+10(x^2+5x)+24-48=(x^2+5x+12)(x^2+5x-2)X^4+Y^4-3X^2Y^2=(x^2+y^2)^2-2x^2y^2-3X^2Y^2=(x^2+y^2+√5xy)(x^2+y^2-√5xy)