(1+3+5+.+2001)-(2+4+6+...2000) 5+8+11+14+...+29+32 2008+2004+2000+...+8+4 (7+9+11+...+25)-((1+3+5+.+2001)-(2+4+6+...2000)5+8+11+14+...+29+322008+2004+2000+...+8+4(7+9+11+...+25)-(5+7+9+..+23)(1+3+5+...+2001)-(2+4+6+...+2000)1+2-
来源:学生作业帮助网 编辑:作业帮 时间:2024/06/24 11:51:53
![(1+3+5+.+2001)-(2+4+6+...2000) 5+8+11+14+...+29+32 2008+2004+2000+...+8+4 (7+9+11+...+25)-((1+3+5+.+2001)-(2+4+6+...2000)5+8+11+14+...+29+322008+2004+2000+...+8+4(7+9+11+...+25)-(5+7+9+..+23)(1+3+5+...+2001)-(2+4+6+...+2000)1+2-](/uploads/image/z/4044522-66-2.jpg?t=%281%2B3%2B5%2B.%2B2001%29-%282%2B4%2B6%2B...2000%29+5%2B8%2B11%2B14%2B...%2B29%2B32+2008%2B2004%2B2000%2B...%2B8%2B4+%EF%BC%887%2B9%2B11%2B...%2B25%EF%BC%89-%EF%BC%88%281%2B3%2B5%2B.%2B2001%29-%282%2B4%2B6%2B...2000%295%2B8%2B11%2B14%2B...%2B29%2B322008%2B2004%2B2000%2B...%2B8%2B4%EF%BC%887%2B9%2B11%2B...%2B25%EF%BC%89-%EF%BC%885%2B7%2B9%2B..%2B23%EF%BC%89%EF%BC%881%2B3%2B5%2B...%2B2001%EF%BC%89-%EF%BC%882%2B4%2B6%2B...%2B2000%EF%BC%891%2B2-)
(1+3+5+.+2001)-(2+4+6+...2000) 5+8+11+14+...+29+32 2008+2004+2000+...+8+4 (7+9+11+...+25)-((1+3+5+.+2001)-(2+4+6+...2000)5+8+11+14+...+29+322008+2004+2000+...+8+4(7+9+11+...+25)-(5+7+9+..+23)(1+3+5+...+2001)-(2+4+6+...+2000)1+2-
(1+3+5+.+2001)-(2+4+6+...2000) 5+8+11+14+...+29+32 2008+2004+2000+...+8+4 (7+9+11+...+25)-(
(1+3+5+.+2001)-(2+4+6+...2000)
5+8+11+14+...+29+32
2008+2004+2000+...+8+4
(7+9+11+...+25)-(5+7+9+..+23)
(1+3+5+...+2001)-(2+4+6+...+2000)
1+2-3+4+4-6+7+8-9+...+58+59-60
(1+3+5+.+2001)-(2+4+6+...2000) 5+8+11+14+...+29+32 2008+2004+2000+...+8+4 (7+9+11+...+25)-((1+3+5+.+2001)-(2+4+6+...2000)5+8+11+14+...+29+322008+2004+2000+...+8+4(7+9+11+...+25)-(5+7+9+..+23)(1+3+5+...+2001)-(2+4+6+...+2000)1+2-
(1+3+5+.+2001)-(2+4+6+...2000)
=1+(3-2)+(5-4)+...+(2001-2000)=1+1+...+1=1001
等比数列求和公式(a1+an)n/2
5+8+11+14+...+29+32=(5+32)*10/2=185
2008+2004+2000+...+8+4=(2008+4)*512/2=2012*256=515072
(7+9+11+...+25)-(5+7+9+..+23)=(7+9+11+...+23)+25-5-(7+9+11+...+23)=25-5=20
(1+3+5+...+2001)-(2+4+6+...+2000)
=1+(3-2)+(5-4)+.+(2001-2000)=1+1+...+1(一共1001个1)=1001
应该是
1+2-3+4+5-6+7+8-9+...+58+59-60
=1+2+3+.+60-2(3+6+9+.+60)
=(1+60)60/2-2(3+60)*20/2
=61*30-63*20
=1830-1260
=570