M
mimidethuong72


cac ban oi jup mink bai nay voi
bÀI 1:tính
1+(1+2)+(1+2+3)+(1+2+3)+(1+2+3+4)+........+?(1+2+3+4+5+.....+97+98)
C= ____________________________________________________________
1.2+2.3+3.4+..........+98.99
BÀI 2:tính
100-(1+1/2+1/3+........+1/100)
________________________
1/2+2/3+3/4+...........+99/100
BÀI 3:Chứng minh rằng
S= 1/2^2+1/3^2+1/4^2+..............+1/100^2 < 1
BÀI 4:Chứng minh rằng
P= 1+1/1!+1/2!+1/3!+...................+1/1994! <3