你好!
lim [an²/(3n+1) - n]
= lim [an² - n(3n+1)]/(3n+1)
= lim [(a-3)n² - n] / (3n+1)
极限存在,必有a-3=0即a=3
极限为 -1/3 即 b = -1/3
故 a+b = 8/3
你好!
lim [an²/(3n+1) - n]
= lim [an² - n(3n+1)]/(3n+1)
= lim [(a-3)n² - n] / (3n+1)
极限存在,必有a-3=0即a=3
极限为 -1/3 即 b = -1/3
故 a+b = 8/3