1.Tìm x
a. \(\sqrt{x+5}=1+\sqrt{x}\)
b. \(\sqrt{x}+\sqrt{1-x}=1\)
c. \(\sqrt{3-x}+\sqrt{x-5}=10\)
2. Tính
\(A=\sqrt{5-2\sqrt{6}}+\sqrt{5+2\sqrt{6}}\)
\(B=\left(4+\sqrt{15}\right).\left(\sqrt{10}-\sqrt{6}\right).\sqrt{4-\sqrt{15}}\)
\(C=\sqrt{7-2\sqrt{10}-\sqrt{7+2\sqrt{10}}}\)