Question

$\sqrt{6} \times \sqrt{15} + \sqrt{40}$

Answer 1

$\sqrt{6} \times \sqrt{15} + \sqrt{40} = \\ \\ \sqrt{6\times15} + \sqrt{40} = \\ \\ \sqrt{90} + \sqrt{40} = \\ \\ \sqrt{2.3^2.5} + \sqrt{2^2.2.5} = \\ \\ 3 \sqrt{10} +2 \sqrt{10} =5 \sqrt{10} \\ \\ ------------------------ \\ \\ pode ~~assim~tamb\'em \\ \\ \sqrt{9.10} + \sqrt{4.10} = \\ \\ 3 \sqrt{10} +2 \sqrt{10} =5 \sqrt{10}$

Answer 2

$\sqrt{6} + \sqrt{15} + \sqrt{40} = \\ \\ \sqrt{6} + \sqrt{15} + \sqrt{2^{2} } \sqrt{10} = \\ \\ \sqrt{6} + \sqrt{15} + 2 \sqrt{10}$