a/ \(\Rightarrow2x^2-3x-11=x^2-1\)
\(\Leftrightarrow x^2-3x-10=0\Rightarrow\left[{}\begin{matrix}x=5\\x=-2\end{matrix}\right.\)
Thay 2 nghiệm vào cả 2 căn thức thấy đều xác định
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b/ \(\left\{{}\begin{matrix}x\ge-1\\2x^2+3x-5=\left(x+1\right)^2\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge-1\\x^2+x-6=0\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x\ge-1\\\left[{}\begin{matrix}x=2\\x=-3\left(l\right)\end{matrix}\right.\end{matrix}\right.\) \(\Rightarrow x=2\)
c/
\(\Leftrightarrow x^2+4x+4=3x^2-5x+14\)
\(\Leftrightarrow2x^2-9x+10=0\)
\(\Rightarrow\left[{}\begin{matrix}x=2\\x=\frac{5}{2}\end{matrix}\right.\)
d/
\(\Leftrightarrow\left\{{}\begin{matrix}-x-9\ge0\\\left(x-1\right)\left(2x-3\right)=\left(-x-9\right)^2\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\le-9\\2x^2-5x+3=x^2+18x+81\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\le-9\\x^2-23x-78=0\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=26\left(ktm\right)\\x=-3\left(ktm\right)\end{matrix}\right.\)
Vậy pt vô nghiệm
