Respostas

2014-06-23T15:27:37-03:00
N² - (n-1)²
n² - (n-1)x(n-1) (aplicamos a distributiva aqui)
n² - (n²-n-n+2)
n² - (n²-2n+2)
n² - n² + 2n -2
2n-2