Question

Обчислити 62: (9-√19)+4: (√23+√19) – 7: (√23+4)

Answer 1

вот так вот легко решается

Answer 2

$displaystyle frac{62}{9-sqrt{19}} +frac{4}{sqrt{23}+sqrt{19}} -frac{7}{sqrt{23}+4} =\\\ =frac{62(9+sqrt{19})}{(9-sqrt{19})(9+sqrt{19})} +frac{4(sqrt{23}-sqrt{19})}{(sqrt{23}+sqrt{19})(sqrt{23}-sqrt{19})} -frac{7(sqrt{23}-4)}{(sqrt{23}+4)(sqrt{23}-4)} = \\\ =frac{62(9+sqrt{19})}{81-19} +frac{4(sqrt{23}-sqrt{19})}{23-19} -frac{7(sqrt{23}-4)}{23-16}= \\\ =frac{62(9+sqrt{19})}{62} +frac{4(sqrt{23}-sqrt{19})}{4} -frac{7(sqrt{23}-4)}{7}=$

$=9+sqrt{19}+sqrt{23}-sqrt{19}-(sqrt{23}-4) =9+sqrt{23}-sqrt{23}+4= 13$