Question

căn x+3 - 2 căn x = căn 2x+2 - căn 3x+1

Answer 1

\(\Leftrightarrow\sqrt{x+3}-2-2\sqrt{x}+2=\sqrt{2x+2}-2+2-\sqrt{3x+1}\)

=>\(\dfrac{x+3-4}{\sqrt{x+3}+2}-2\left(\sqrt{x}-1\right)=\dfrac{2x+2-4}{\sqrt{2x+2}+2}+\dfrac{4-3x-1}{2+\sqrt{3x+1}}\)

=>\(\dfrac{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}{\sqrt{x+3}+2}-2\left(\sqrt{x}-1\right)=\dfrac{2\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}{\sqrt{2x+2}+2}-\dfrac{3\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}{2+\sqrt{3x+1}}\)

=>\(\left(\sqrt{x}-1\right)\left(\dfrac{\sqrt{x}+1}{\sqrt{x+3}+2}-2-\dfrac{2\sqrt{x}+2}{\sqrt{2x+2}+2}+\dfrac{3\sqrt{x}+3}{2+\sqrt{3x+1}}\right)=0\)

=>căn x-1=0

=>x=1

Answer 2