Question

Решите 2 примера подалуйста срочно!!!

Answer 1

(a +- b)² = a² +- 2ab + b²

(a - b)(a + b) = a² - b²

√a² = |a|

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(√(7 - 2√6) - √(7 + 2√6))² =

(√(6 - 2√6 + 1) - √(6 + 2√6 + 1))² =

(√(√6² - 2√6 + 1²) - √(√6² + 2√6 + 1))² =

(√(√6 - 1)² - √(√6 + 1)²)² =

(|√6 - 1| - |√6 + 1|)² = (√6 - 1 - √6 - 1)² = (-2)² = 4

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1/(3√7 - 7) - 1/(7 + 3√7) =

(7 + 3√7 - (3√7 - 7))/((3√7 - 7)(7 + 3√7)) =

(7 + 3√7 - 3√7 + 7)/((3√7)² - 7²) =

14/(9*7 - 49) = 14/(63 - 49) = 14/14 = 1