(11a+3b)(11a-3b)-(11a-3b)(3b-11a)
(11a+3b)(11a-3b)+(11a+3b)(11a-3b)
121a²-9b²+121a²-9b²=242a²-18b²
Формула:(a+b)(a-b)=a²-b²
(11a+3b)(11a-3b)-(11a-3b)(3b-11a)
(11a+3b)(11a-3b)+(11a+3b)(11a-3b)
121a²-9b²+121a²-9b²=242a²-18b²
Формула:(a+b)(a-b)=a²-b²