\(x^3-x^2-5x+125\)
\(=\left(x+5\right)\left(x^2-5x+25\right)-x\left(x+5\right)\)
\(=\left(x+5\right)\left(x^2-6x+25\right)\)
p/s: chúc bạn học tốt
=(x^3+125)-(x^2+5x)
=(x^3+5^3)-x(x+5)
=(x+5)(x^2-5x+25)-x(x+5)
=x+5(x^2-5x+25x)-x(x+5)
=x+5(x^2-5x+25-x)
=x+5(x^2-7x+25)
chúc bn hk tốt!!!