c: ĐKXĐ: \(x\in R\)
\(\sqrt{x^2-10x+25}=x+2\)
=>\(\sqrt{\left(x-5\right)^2}=x+2\)
=>\(\left|x-5\right|=x+2\)
=>\(\left\{{}\begin{matrix}x>=-2\\\left(x-5\right)^2=\left(x+2\right)^2\end{matrix}\right.\)
=>\(\left\{{}\begin{matrix}x>=-2\\x^2-10x+25=x^2+4x+4\end{matrix}\right.\)
=>\(\left\{{}\begin{matrix}x>=-2\\-14x=-21\end{matrix}\right.\)
=>x=3/2(nhận)
d: ĐKXĐ: x>=0
\(x+\sqrt{x}-6=0\)
=>\(x+3\sqrt{x}-2\sqrt{x}-6=0\)
=>\(\left(\sqrt{x}+3\right)\left(\sqrt{x}-2\right)=0\)
=>\(\sqrt{x}-2=0\)
=>\(\sqrt{x}=2\)
=>x=4(nhận)
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