Normal
DKXĐ:\[x\geq 0\](1)\[\Leftrightarrow x+x+9+2\sqrt{x(x+9)}=x+1+x+4+2\sqrt{(x+1)(x+4)}\]\[\Leftrightarrow 2+\sqrt{x(x+9)}=\sqrt{(x+1)(x+4)}\]\[\Leftrightarrow 4+x(x+9)+4\sqrt{x(x+9)}=(x+1)(x+4)\]\[\Leftrightarrow \sqrt{x(x+9)}+x=0\](2)Do \[\sqrt{x(x+9)}\geq 0; x\geq 0\] nên (2)\[\Leftrightarrow x=0\] (thỏa mãn)
DKXĐ:\[x\geq 0\]
(1)\[\Leftrightarrow x+x+9+2\sqrt{x(x+9)}=x+1+x+4+2\sqrt{(x+1)(x+4)}\]
\[\Leftrightarrow 2+\sqrt{x(x+9)}=\sqrt{(x+1)(x+4)}\]
\[\Leftrightarrow 4+x(x+9)+4\sqrt{x(x+9)}=(x+1)(x+4)\]
\[\Leftrightarrow \sqrt{x(x+9)}+x=0\](2)
Do \[\sqrt{x(x+9)}\geq 0; x\geq 0\] nên (2)\[\Leftrightarrow x=0\] (thỏa mãn)
