Question

giải phương trình sau:x(x+3)²-3x=(x+2)³+1

Answer 1

x(x²+6x+9) - 3x= x³+6x²+12x+8+1

\(\Leftrightarrow\)x³+6x²+9x-3x=x³+6x²+12x+9

\(\Leftrightarrow\)6x=12x+9

\(\Leftrightarrow\)6x=-9

\(\Leftrightarrow\)x=-3/2

Vậy phương trình có 1 nghiệm duy nhất x=-3/2

Answer 2

x(x + 3)^2  - 3x = (x + 2)^3 + 1

<=> x(x^2 + 6x + 9) = x^3 + 6x^2 + 12x + 8 + 1

<=> x^3 + 6x^2 + 9x = x^3 + 6x^2 + 12x + 9

<=> 3x + 9 = 0

<=> 3x = -9

<=> x = -3

Answer 3

\(x\left(x+3\right)^2-3x=\left(x+2\right)^3+1\)

\(\Leftrightarrow x\left(x^2+6x+9\right)=x^3+6x^2+12x+8+1\)

\(\Leftrightarrow x^3+6x^2+9x=x^3+6x^2+12x+9\)

\(\Leftrightarrow3x+9=0\)

\(\Leftrightarrow3x=-9\)

\(\Leftrightarrow x=-3\)