Các câu hỏi tương tự
Tinh:a)N=1+3^2+...+3^100;b)P=1+5^3+5^6+5^9+...+5^99
tinh:A=1+2-3-4+5+6-7-8+9+....+2006-2007-2008+2009+2010-2011-2012+2013+2014
tinh:A=1+2+22+23+................+260
B=3+33+35+..........................+381
C=23+26+29+.......................+290
D=3100-399+398-..................-3
E=-1/3.(1+2+3)-1/4.(1+2+3+4)-...-1/50.(1+2+3+4+...+50)
E=-1/3.(1+2+3)-1/4.(1+2+3+4)-...-1/50.(1+2+3+4+...+50)
Giúp mình với
50-(1+1/3+........+1/50)=1/2+2/3+3/4+.......+49/50
Tính tổng :\(S=1+\frac{1}{2}.\left(1+2\right)+\frac{1}{3}.\left(1+2+3\right)+\frac{1}{4}.\left(1+2+3+4\right)+....+\frac{1}{50}.\left(1+2+3+4+....+50\right)\)
(1+1/2)(+1+1/2^2)(1+1/2^3)...(1+1/2^50)
tinh C =-1/3(1+2+3)-.....-1/50(1+2+3+...+50)