Question

tập các giá trị của x thỏa man 

\(4\left(x-1\right)^2-9\left(x+2\right)^2=0\)

Answer 1

\(4\left(x-1\right)^2-9\left(x+2\right)^2=0\)

\(\Leftrightarrow\left[2\left(x-1\right)\right]^2-\left[3\left(x+2\right)\right]^2=0\)

\(\Leftrightarrow\left[2\left(x-1\right)+3\left(x+2\right)\right]\left[2\left(x-1\right)-3\left(x+2\right)\right]=0\)

\(\Leftrightarrow\left(2x-2+3x+6\right)\left(2x-2-3x-6\right)=0\)

\(\Leftrightarrow\left(5x+4\right)\left(-x-8\right)=0\)

\(\Leftrightarrow\left[\begin{array}{nghiempt}5x+4=0\\-x-8=0\end{array}\right.\)\(\Leftrightarrow\left[\begin{array}{nghiempt}x=-\frac{4}{5}\\x=-8\end{array}\right.\)