Упростите (2n+1)²+(2n²+2n)²-(2n²+2n+1)²

Question

Упростите (2n+1)²+(2n²+2n)²-(2n²+2n+1)²

Answer 1

Упрощаем по формулам:
(a+b)² = a² + b²+ 2ab  и  (a+b+c)²= a²+b²+c²+2ab+2bc+2ca: