\(\sqrt{x}+\sqrt{1-x}=1\)
\(\Leftrightarrow\left(\sqrt{x}+\sqrt{1-x}\right)^2=1\)
\(\Leftrightarrow x+2\sqrt{x\left(1-x\right)}+1-x=1\)
\(\Leftrightarrow2\sqrt{x\left(1-x\right)}=0\)
\(\Leftrightarrow x\left(1-x\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=1\end{matrix}\right.\)