Explicație pas cu pas:
[tex]x = \sqrt{144} +2 \sqrt{18} - ( \sqrt{3})^{2} [/tex]
[tex]y = {(\sqrt{5} - \sqrt{3})}^{2} - \sqrt{72} + {(\sqrt{5} + \sqrt{3})}^{2} - 7[/tex]
a)
[tex]x = \sqrt{144} +2 \sqrt{18} - ( \sqrt{3})^{2} = 12 + 2 \times 3 \sqrt{2} - 3 = 9 + 6 \sqrt{2} [/tex]
b)
[tex]y = {(\sqrt{5} - \sqrt{3})}^{2} - \sqrt{72} + {(\sqrt{5} + \sqrt{3})}^{2} - 7 = 5 - 2 \sqrt{15} + 3 - 6 \sqrt{2} + 5 + 2 \sqrt{15} + 3 - 7 = 9 - 6 \sqrt{2} [/tex]
[tex]xy = (9 + 6 \sqrt{2}) \times (9 - 6 \sqrt{2} = {9}^{2} - {(6 \sqrt{2}) }^{2} = 81 - 72 = 9[/tex]
