Các câu hỏi tương tự
bài 2: tính nhanh :
a) 3/8 + 7/12 + 10/16 + 10/24 b) 4/6 + 7/13 + 17/9 + 19/13 + 1/9 + 14/6
c) 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56
tính nhanh:
a)1/2+1/6+1/12+1/20+1/30+1/42
b)1/2+1/4+1/8+1/16+1/32
c)1/2+1/4+1/8+...+1/256
C=1/2+1/4+1/8+1/16+1/32+1/64+1/128
D=1/2+1/6+1/12+1/20+1/30+1/42
Giải đầy đủ rõ ràng nha mn
B= 6/1.3+6/3.5+6/3.7+......+6/97.99
C=1/2 + 1/6 + 1/12 + 1/ 20 + 1/30 + 1/42
D= 1/2 + 1/4 + 1/8 + 1/16 + 1/32 + 1/64 + 1/128
Giúp mik vs nha mn ^^
(/ là phần, * là cộng)
Tính nhanh:
A= 1/2 + 1/6 + 1/12 + 1/20 + 1/30 + 1/42 + 1/56 + 1/72
B= 1/5*6 + 1/6*7 + 1/7*8 +........+ 1/24*25
C= 2/3*5 + 3/5*8 + 11/8*19 + 13/19*32 + 25/32*57 + 30/57*87
chứng tở rằng 1 + 1/2 + 1/3 + 1/4 + 1/5 + 1/6 + 1/7 + 1/8 + 1/9 + 1/10 + 1/11 + 1/12 + 1/13 + 1/14 + 1/15 + 1/16 + 1/17 + 1/18 + 1/ 19 + 1/20 + 1/21 + 1/22 + 1/ 23 + 1/24 + 1/25 + 1/26 + 1/27 + 1/28 + 1/29 + 1/30 + 1/31 + 1/32 < 3
B= 2/20+2/30+2/42+2/56+2/90
C=(1/22-1)*(1/32-1)*...(1/100-1)
bài 1 : 1/1x2+1/2x3+1/3x4+1/5x6+1/6x7
Bài 2:1/2+1/6+1/12+1/30+1/42+1/56+1/72
Bài 3: (1-1/2)x(1-1/3)x....x(1-2019)
Bài 4:1/4+1/8+1/16+1/32+1/64+1/128+1/256+1/512
8/9 - 1/72 - 1/56 - 1/42 - 1/30 - 1/20 - 1/12 - 1/6 - 1/2