Question

(x-2)³-(x-3)(x²+3x+9)+6(x+1)²=49

Answer 1

=> x³-6x²+12x-8-(x³-27) + 6(x²+2x+1) = 49

=> >x3 -6x2+12x-8-x3+27+6x2+12x+6=49

=>24x+25=49

<=>24x=24

<=>x=1

Xong rồi đó dòng thứ 2 do chị đang bận nên em tự hiểu là dấu mũ nha

Answer 2

\(\left(x-2\right)^3-\left(x-3\right)\left(x^2+3x+9\right)+6\left(x+1\right)^2=49\)

\(\Rightarrow x^3-3x^22+3x2^2-2^3-x^3+3^3+6\left(x^2+2x+1\right)=49\)

\(\Rightarrow x^3-6x^2+12x-8-x^3+27+6x^2+12x+6=49\)

\(\Rightarrow24x+25=49\)

\(\Rightarrow24x=49-25=24\)

\(\Rightarrow x=1\)