Question

giúp e với đang cần thực sự gấp ạ! e cảm ơnnn

Answer 1

Answer 2

a: \(\left(x+3\right)^3-x\left(3x+1\right)^2+\left(2x+1\right)\left(4x^2-2x+1\right)-3x^2=54\)

\(\Leftrightarrow x^3+9x^2+27x+27-x\left(9x^2+6x+1\right)+8x^3+1-3x^2=54\)

\(\Leftrightarrow9x^3+6x^2+27x+28-9x^3-6x^2-x=54\)

hay x=1

b: Ta có: \(\left(x-3\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+6\left(x+1\right)^2+3x^2=-33\)

\(\Leftrightarrow x^3-9x^2+27x-27-x^3+27+6x^2+12x+6+3x^2=-33\)

hay x=-1

Answer 3

a. (x + 3)³ - x(3x + 1)² + (2x + 1)(4x² - 2x + 1) - 3x² = 54

<=> x³ + 9x² + 27x + 27 - x(9x² + 6x + 1) + 8x³ - 4x² + 2x + 4x² - 2x + 1 - 3x² = 54

<=> x³ + 9x² + 27x + 27 - 9x³ - 6x² - x + 8x³ - 4x² + 2x + 4x² - 2x + 1 - 3x² = 54

<=> x³ - 9x³ + 8x³ + 9x² - 6x² - 4x² + 4x² - 3x² + 27x - x + 2x - 2x = 26

<=> 26x = 26

<=> x = 1