Question

розв'язати рiвняння:x³+2x²-18x-36=0

Answer 1

Ответ:

х^3+2х^2-18х-36=0​

x^2(x+2)-18(x+2)=0

(x^2-18)(x+2)=0

x^2-18=0

x^2=18

x=±3√2

x+2=0

x= -2

Объяснение:

Answer 2

Ответ:

${x}^{3} + {2x}^{2} - 18x - 36 = 0 \\ ( {x}^{3} + {2x}^{2} ) - (18x + 36) = 0 \\ {x}^{2} \times (x + 2) - 18 \times (x + 2) = 0 \\ (x + 2)( {x}^{2} - 18) = 0 \\ \\ x + 2 = 0 \\ x1 = - 2 \\ \\ {x}^{2} - 18 = 0$

${x}^{2} - 18 = 0 \\ {x}^{2} = 18 \\ x1 = \sqrt{18 } = \sqrt{9 \times 2} = 3 \sqrt{2 } \\ x2 = - 3 \sqrt{2}$