Explicație pas cu pas:
[tex]a = 2\left( \frac{ {3}^{2} + {4}^{2} }{ {5}^{2} } + \frac{ {25}^{2} - {10}^{2} }{ {20}^{2} } \right) \\ = 2\left( \frac{ 9 + 16 }{25} + \frac{625 - 225}{400} \right) \\ = 2\left( \frac{25}{25} + \frac{400}{400} \right) = 2(1 + 1) \\ = 2 \times 2 = 4[/tex]
[tex] \sqrt{a} = \sqrt{4} = 2[/tex]
