Bài 2:
a: Ta có: \(4x^2-9-2\left(2x+3\right)=0\)
\(\Leftrightarrow\left(2x+3\right)\left(2x-5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-\dfrac{3}{2}\\x=\dfrac{5}{2}\end{matrix}\right.\)
b: Ta có: \(\left[\left(x+2\right)\left(1-x\right)-\left(x^2-4\right)\right]:\left(x+2\right)=1\)
\(\Leftrightarrow x-x^2+2-2x-x^2+4=x+2\)
\(\Leftrightarrow-2x^2-x+6-x-2=0\)
\(\Leftrightarrow-2x^2-2x+4=0\)
\(\Leftrightarrow x^2+x-2=0\)
\(\Leftrightarrow\left(x+2\right)\left(x-1\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=-2\left(loại\right)\\x=1\left(nhận\right)\end{matrix}\right.\)
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