\(\left(3x-2\right)\left(x+1\right)^2\left(3x+8\right)=-16\)
\(\Leftrightarrow\left[\left(3x-2\right)\left(3x+8\right)\right]\left[9\left(x+1\right)^2\right]=-16.9\)
\(\Leftrightarrow\left(9x^2+18x-16\right)\left(9x^2+18x+9\right)=-144\)
\(\Leftrightarrow\left(9x^2+18x\right)^2-7\left(9x^2+18x\right)-144=-144\)
\(\Leftrightarrow\left(9x^2+18x\right)^2-7\left(9x^2+18x\right)=0\)
\(\Leftrightarrow\left(9x^2+18x\right)\left(9x^2+18x-7\right)=0\)
\(\Leftrightarrow9x\left(x+2\right)\left(3x-1\right)\left(3x+7\right)=0\)
Tập nghiệm của pt là: \(S=\left\{0;-2;\frac{1}{3};\frac{-7}{3}\right\}\)
\(\left(3x-2\right)\left(x-1\right)^2\left(3x+8\right)=-16\)
\(\Leftrightarrow\left[\left(3x-2\right)\left(3x+8\right)\right]\left[9\left(x+1\right)^2\right]=-16.9=-144\)
\(\Leftrightarrow\left(9x^2+18x\right)^2-7\left(9x^2+18x\right)-144=-144\)
\(\Leftrightarrow\left(9x^2+18x\right)^2-7\left(9x^2+18x\right)=0\)
\(\Leftrightarrow\left(9x^2+18x\right)\left(9x^2+18x-7\right)=0\)
\(\Leftrightarrow9x\left(x+2\right)\left(3x-1\right)\left(3x+7\right)=0\)
Tập nghiệm của phương trình là : \(S=\left\{0;-2;\frac{1}{3};\frac{-7}{3}\right\}\)
Anh Ngáo coppy trắng trợn là ko tốt :v
\(\left(3x-2\right)\left(x+1\right)^2\left(3x+8\right)=-16\)
\(9x^4+18x^3+9x^2+24x^3+48x^2+24x-6x^3-12x^2-6x-16x^2-32x-16=-16\)
\(9x^4+36x^3+29x^2-14x-16=-16\)
\(9x^4+36x^3+29x^2-14x=0\)
\(x\left(9x^3+36x^2+29x-14\right)=0\)
\(x=0;-\frac{7}{3};\frac{1}{3};-2\)
