Question

So sánh A.7 + 2 căn 2 ... 10

B. Căn 2 + căn 3 ... 3

Answer 1

a: 2căn 2=căn 8<căn 9=3

=>\(2\sqrt{2}+7< 3+7=10\)

b: \(\left(\sqrt{2}+\sqrt{3}\right)^2=5+2\sqrt{6}\)

\(3^2=9=5+4\)

mà \(2\sqrt{6}>4\)

nên \(\left(\sqrt{2}+\sqrt{3}\right)^2>3^2\)

=>\(\sqrt{3}+\sqrt{2}>3\)