(1+2+3+4+.........+10099+10000+10001) - 225
=\(\frac{10001.\left(10001+1\right)}{2}\)-5153632
=50015001-5153632
=44861369
(1+2+3+4+.........+10099+10000+10001) - 225
=\(\frac{10001.\left(10001+1\right)}{2}\)-5153632
=50015001-5153632
=44861369
Cho A= 26/25 + 37/36 + 50/49 +...+ 10001/10000 . Chứng minh rằng: 96/1/6 < A < 96/1/4
1+2+3+....+10000=
1+3+5+7+.....+10000
2+4+6+8+10+.......+10000
GIÚP MÌNH GIẢI BÀI NÀY VỚI
a)1/10000+13/1000+25/10000+.....................+97/10000+109/10000
b)4/3 *2019*0,75
c) 4*5+0,25*1/5*1/2*2
d)2003*1999-2003*999/2004*999+1004
Đầu bài là tính nhanh
bài 1. tính
a, (1-1/4).(1-1/9)...(1-1/10000)
b, 3/4.8/9...9999/10000
c, 3-1/5+3/10/2+1/4-3/5
d, 2/3+2/5+2/17-2/293/3/7+3/5+3/17-3/293
B=5/6+19/20+41/42+......+10099/10100 và C= 3/2+13/12+31/30+..........+9901/9900
Tính C - B
Tính A-B biết
A=3/2+13/12+31/30+...+9901/9900
B=5/6+19/20+41/42+...+10099/10100
1 + 2 + 3 + 4 + ... + 10000
So sánh:
a ) A = 17 18 + 1 17 19 + 1 v à B = 17 17 + 1 17 18 + 1 ; b ) C = 100 100 + 1 100 90 + 1 v à D = 100 99 + 1 100 89 + 1 ;
1-2+3-4+....+999-10000