8. Найдите значение выражения 1/(7+√47) + 1/(7-√47).

To add the fractions, find a common denominator, which is the product of the two denominators: (7+√47)(7-√47).

Numerator becomes: (7-√47) + (7+√47) = 14.

Denominator becomes: 7² - (√47)² = 49 - 47 = 2.

The expression simplifies to 14/2 = 7.