Question

(radical din 10 - 3) totu la a 2 +radical din 20 x radical din 18,

Answer 1

   
[tex]\displaystyle\\ \left(\sqrt{10} -3\right)^2+ \sqrt{20} \times \sqrt{18} =\\\\ =\left(\sqrt{10}\right)^2 - 2\times\sqrt{10}\times 3+(-3)^2+\sqrt{4\times 5}\times\sqrt{9\times 2}=\\ =10 - 6\sqrt{10}+9+2\sqrt{5}\times3\sqrt{2}=\\ =10+9 - 6\sqrt{10}+2\times 3 \times \sqrt{5}\times\sqrt{2}=\\\\ =19 - \underline{6\sqrt{10}} + \underline{6\sqrt{10}} = \boxed{\bf 19} [/tex]