a) 4√6 - √24 + √54 = 4√6 - √(4 * 6) + √(9 * 6) = 4√6 - 2√6 + 3√6 = (4 - 2 + 3)√6 = 5√6
б) (√54 - √24) * √6 = (√(9 * 6) - √(4 * 6)) * √6 = (3√6 - 2√6) * √6 = √6 * √6 = 6
в) (4√3 + 5)² = (4√3)² + 2 * 4√3 * 5 + 5² = 16 * 3 + 40√3 + 25 = 48 + 40√3 + 25 = 73 + 40√3
г) (3√2 + 2√5) * (3√2 - 2√5) = (3√2)² - (2√5)² = 9 * 2 - 4 * 5 = 18 - 20 = -2