[tex]\\D \in N\\\\x, y, z - \text{kolejne liczby naturalne}\\y=x+1\\z=x+2\\\\xyz=6x\\x(x+1)(x+2)=6x\\x(x^2+2x+x+2)=6x\\x(x^2+3x+2)=6x\\x^3+3x^2+2x=6x\\x^3+3x^2+2x-6x=0\\x^3+3x^2-4x=0\\x(x^2+3x-4)=0\\\\x=0 \notin D\\x^2+3x-4=0\\\Delta=3^2-4*1*(-4)=9+16=25\\\sqrt{\Delta}=5\\x_1=\frac{-3-5}{2}=\frac{-8}2=-4 \notin D\\x_2=\frac{-3+5}2=\frac22=1\\\\Odp. :\\x=1\\y=2\\z=3[/tex]
