Question

x(x^2 - 7) = 6

Спасибо заранее!

Answer 1

x(x^2-7)=6

x^3-7x=6

x^3-7x-6=0

x^3+x^2-x^2-x-6x-6=0

x^2+(x+1)-x(x+1)-6(x+1)=0

(x+1)*(x^2-x-6)=0

(x+1)*(x^2+2x-3x-6)=0

(x+1)*(x(x+2)-3(x+2)=0

(x+1)*(x+2)*(x-3)=0

x+1=0

x+2=0

x-3=0

x= -1

x= -2

x= 3

X1= -2 , X2= -1 , X3=3