1+2+3+4+.+n=2005003 则自然数n=
问题描述:
1+2+3+4+.+n=2005003 则自然数n=
答
(1+n)*n=2005003*2 n^2+n+1/4=4010006+0.25 (n+0.5)=2002.5^2 n=2002
1+2+3+4+.+n=2005003 则自然数n=
(1+n)*n=2005003*2 n^2+n+1/4=4010006+0.25 (n+0.5)=2002.5^2 n=2002