a: ĐKXD: x>0
\(y=\frac{x^2+\sqrt{x}}{x-\sqrt{x}+1}+1-\frac{2x+\sqrt{x}}{\sqrt{x}}\)
\(=\frac{\sqrt{x}\left(\sqrt{x}+1\right)\left(x-\sqrt{x}+1\right)}{x-\sqrt{x}+1}+1-\frac{\sqrt{x}\left(2\sqrt{x}+1\right)}{\sqrt{x}}\)
\(=\sqrt{x}\left(\sqrt{x}+1\right)+1-2\sqrt{x}-1=x+\sqrt{x}-2\sqrt{x}=x-\sqrt{x}\)
b: y=2
=>\(x-\sqrt{x}=2\)
=>\(x-\sqrt{x}-2=0\)
=>\(\left(\sqrt{x}-2\right)\left(\sqrt{x}+1\right)=0\)
=>\(\sqrt{x}-2=0\)
=>\(\sqrt{x}=2\)
=>x=4(nhận)
c: x>1
=>\(\sqrt{x}>1\)
=>\(\sqrt{x}-1>0\)
=>\(\sqrt{x}\left(\sqrt{x}-1\right)>0\)
=>y>0
=>|y|=y
=>y-|y|=0
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