\(x^2-y-y^2-x=\left(x-y\right)\left(x+y\right)-\left(x+y\right)=\left(x+y\right)\left(x-y-1\right)\)

x² - y - y² - x

= (x² - y²) - x - y

= (x - y)(x + y) - (x + y)

= (x - y - 1)(x + y)

\(=x\left(x-4\right)+5\left(x-4\right)=\left(x+5\right)\left(x-4\right)\)

x(x-4)+5(x-4)

(x+5)(x-4)

x² - 5x + 5

= x² - 5(x + 1)

= x² - \(\left[\sqrt{5\left(x+1\right)}\right]^2\)

= [x - \(\sqrt{5\left(x+1\right)}\)][x + \(\sqrt{5\left(x+1\right)}\)]

\(=\left(x^2\right)^2-\left(y^3\right)^2=\left(x^2-y^3\right)\left(x^2+y^3\right)\)

Bạn trình bầy rõ ràng chút đi. Mk chẳng hiểu gì cả.

\(-25x^6-y^8+10x^3y^4\\ =-\left(25x^6-10x^3y^4+y^8\right)\\ =-\left[\left(5x^3\right)^2-2\cdot5x^3\cdot y^4+\left(y^4\right)^2\right]\\ \\ =\left(5x^3-y^4\right)^2\)

x^6 - y^6 = (x^3 -y^3) (x^3 + y^3)

              = (x-y)(x^2 + xy + y^2 )(x+y)(x^2 -xy+ y^2)

\(x^6-y^6\)

\(=\left(x^3-y^3\right)\left(x^3+y^3\right)\)

\(=\left(x.y\right)\left(x^2+xy+y^2\right)\left(x.y\right)\left(x^2-xy+y^2\right)\)

Chúc bạn học tốt!

thank you