Question

fie numerele a=2√5, b=5√2, c=√18 determinati daca 120 l de apa incap intr-un acvariu de forma unui paralelipiped dreptunghic de dimensiunile a, b, c (exprimate in decimetri

Answer 1

   
[tex]V = a \times b \times c = \\ =2 \sqrt{5} \times 5 \sqrt{2} \times \sqrt{18} = \\ =2 \sqrt{5} \times 5 \sqrt{2} \times 3\sqrt{2} = \\ =2 \sqrt{5} \times 5 \times 3(\sqrt{2})^2= \\ =2 \sqrt{5} \times 15 \times 2= \\ =2 \sqrt{5} \times 30= \\ =2 \times 30 \times \sqrt{5} = \\ =60 \sqrt{5} \ \textgreater \ 60 \sqrt{4} =60 \times 2 = 120 ~dm^3 \\ \\ \Longrightarrow ~~ \boxed{V \ \textgreater \ 120~dm^3} \\ \\ 1 ~dm^3 = 1~ litru \\ \\ \Longrightarrow ~ \texttt{In acvariu incap mai mult de 120 litrii de apa.}[/tex]