bài này dạng lớp 6 nha
1 x 3 x5 x.....x199=1.2.3.......200/2.4.6.....200=1.2.3....200/1.2.2.2.2.3....100.2=1.2.3......100.....200/1.2.3....100.2.2......2=101.....200/2.2...2
=101/2.102/2.....200/2
vậy ....
CMR: 1-1/2+1/3-1/4+....+1/199-1/200=1/101-1/102+...+1/200
cho A=1/101+1/102+1/103+...+1/199+1/200 cmr 5/8<a<3/4
CM B=1-1/2+1/3-1/4+.....+1/199-1/200 = 1/101+1/102+.....+1/199+1/200
Chứng minh :1-1/2+1/3-1/4+...+1/199-1/200=1/101+1/102+....+1/200
Chứng tỏ rằng: 1-1/2+1/3-1/4+...+1/99-1/200=1/101+1/102+...+1/199+1/200
chung minh rang 1-1/2+1/3-1/4+...+1/99-1/200=1/101+1/102+...+1/199+1/200
chứng tỏ rằng 1-1/2+1/3-1/4+.....+1/99-1/200=1/101+1/102+...+1/199+1/200
Cho A = 1 x 2 + 2 x 3 + 3 x 4 + 4 x 5 + ... + 100 x 101
và B = 1 x 3 + 2 x 4 + 3 x 5 + 4 x 6 + ... + 100 x 102
Vậy B - A = ?
chứng tỏ rằng 1-\(\frac{1}{2}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{199}-\frac{1}{200}=\frac{1}{101}+\frac{1}{102}+...+\frac{1}{199}+\frac{1}{200}\)
