Question

\(\)SO SÁNH 

a) 15 và \(\sqrt{235}\) 

b) \(\sqrt{7}\)+  \(\sqrt{15}\)và 7

Answer 1

a) \(15=\sqrt{225}\)

\(\sqrt{235}=\sqrt{235}\)

vi \(225< 235\)nen \(\sqrt{225}< \sqrt{235}\)

   vay \(15< \sqrt{235}\)

Answer 2

Câu b) 

Ta có \(\sqrt{7}< \sqrt{9}\Leftrightarrow\sqrt{7}< 3\)

\(\sqrt{15}< \sqrt{16}\Leftrightarrow\sqrt{15}< 4\)

Cộng theo vế: \(\sqrt{7}+\sqrt{15}< 3+4\) hay \(\sqrt{7}+\sqrt{15}< 7\)

Answer 3

a,\(15=15\)

    \(\sqrt{235}=15,32970972\)

\(\Rightarrow15< \sqrt{235}\)

b, \(\sqrt{7}+\sqrt{15}=6,518734657\)

     \(7=7\)

\(\Rightarrow\sqrt{7}+\sqrt{15}< 7\)