Question

можна решить без программы photomath
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Answer 1

$\frac{9-\sqrt{5} }{9+\sqrt{5}} +\frac{9+\sqrt{5}}{9-\sqrt{5}} =\frac{(9-\sqrt{5})^2+(9+\sqrt{5})^2}{(9-\sqrt{5})(9+\sqrt{5})} =\frac{81-18\sqrt{5} +5+81+18\sqrt{5} +5}{81-5} = \\ \\ =\frac{172}{76} =\frac{43}{19}=2\frac{5}{19}$