Question

помогите
(√7-2√3) (2√3+√7) - (√6-3√2)^2=

Answer 1

a² - b² = (a - b)(a + b)

(a - b)² = a² - 2ab + b²

(√7-2√3) (2√3+√7) - (√6-3√2)²=√7² - (2√3)² - (√6² - 2√6*3√2 + (3√2)²) = 7 - 12 - 6 + 12√3 - 18 = -29 + 12√3