(n+2)² - n² = 304,
n² + 4n + 4 - n² = 304,
4n+4 = 304,
4*(n+1) = 304,
n+1 = 304/4 = 76,
n = 76 - 1 = 75.
ответ. 75.
(n+2)² - n² = 304,
n² + 4n + 4 - n² = 304,
4n+4 = 304,
4*(n+1) = 304,
n+1 = 304/4 = 76,
n = 76 - 1 = 75.
ответ. 75.