Question

Обчислити:(√(9+4√5) -√(9-4√5) ) ²

Answer 1

(√(9+4√5)-√(9-4√5))²=(√(√5+2)²-√(√5-2)²)²=(|√5+2|-|√5-2|)²=
(√5+2-√5+2)²=4²=16