\(\left(2x+3\right)^2-\left(5x-2\right)^2=0\)
\(\left(2x+3-5x+2\right).\left(2x+3+5x-2\right)=0\)
\(\left(-3x+5\right).\left(7x+1\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}-3x=-5\\7x=-1\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{5}{3}\\x=-\dfrac{1}{7}\end{matrix}\right.\)
\(\left(2x+3\right)^2-\left(5x-2\right)^2=0\)
\(\left(2x+3-5x-2\right)\left(2x+3+5x-2\right)=0\)
\(\left[\left(2x-5x\right)+\left(3-2\right)\right]\left[\left(2x+5x\right)+\left(3-2\right)=0\right]\)
\(\left(-3x+1\right)\left(7x+1\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}-3x+1=0\\7x+1=0\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}-3x=0-1=-1\\7x=0-1=-1\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=\left(-1\right):\left(-3\right)=\dfrac{1}{3}\\x=\left(-1\right):7=\dfrac{-1}{7}\end{matrix}\right.\)
\(\text{Vậy x}\in\left\{\dfrac{1}{3};\dfrac{-1}{7}\right\}\)
