Question

 Porque ?Simplifique a expressão : 3√2 - 2√18 + 3√72 = 15√2 

Answer 1

$3 \sqrt{2} -2 \sqrt{18} +3 \sqrt{72} = \\ \\ 3 \sqrt{2} -2 \sqrt{2.3^2} +3 \sqrt{2.2^2.3^2} = \\ \\ 3 \sqrt{2} -2.3 \sqrt{2} +3.2.3 \sqrt{2} = \\ \\ 3 \sqrt{2} -6 \sqrt{2} +18 \sqrt{2} = \\ \\ 21 \sqrt{2} -6 \sqrt{2} = \\ \\ 15 \sqrt{2}$