Question

Найдите значение выражения:

Answer 1

[x²/(x²-7xy)] /[x/(x²-49y²)]=[x²/(x(x-7y))]/ [x/(x-7y)(x+7x)]=[x/(x-7y)] * [(x-7y)(x+7y)/x]=
=(x+7y)
x=8+7√2, y=2-√2
8+7√2+7*(2-√2)=8+7√2+14-7√2=22