Помогите (6-3√5)(6+3√5)

Question

Помогите (6-3√5)(6+3√5)

Answer 1

Решение
 (6-3√5)(6+3√5) = 6² - (3√5)² = 36 - 45 = - 9

Answer 2

(6-√9х5))6+√9х5)=(6-√45)(6+√45)=(6^2-√45^2=36-45=-9