Tính tổng:
S=\(\left(-\frac{1}{7}\right)\)\(^0\)+ \(\left(-\frac{1}{7}\right)\)\(^1\)+ \(\left(-\frac{1}{7}\right)\)\(^2\)+ .....+ \(\left(-\frac{1}{7}\right)\)\(^{2017}\)
So sánh S và \(\frac{7}{8}\)
a) Tính \(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2017}\)
b) So \(\frac{1}{2!}+\frac{2}{3!}+\frac{3}{4!}+...+\frac{99}{100!}\) với \(1\)
1.Tính tổng :
S = \(\left(\frac{-1}{7}\right)^o+\left(\frac{-1}{7}\right)^1+\left(\frac{-1}{7}\right)^2+...+\left(\frac{-1}{7}\right)^{2017}\)
Tính tổng: S= \(\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+...+\left(-\frac{1}{7}\right)^{2007}\)
S=1+(-1/7)^1+(-1/7)^2+...+(-1/7)^2007
=>7S=7+(-1/7)^1+(1/7)^2+...+(-1/7)^2006
=>(7-1)S=6-(1/7)^2007
=>S=1-(-1/7^2007/6)
1/7S=(-1/7)^1+...+(-1/7)2018
1/7S-S=(-1/7)^1+....+(-1/7)^2018-(-1/7)^0-...-(-1/7)^2017
-6/7S=(-1/7)^2018-1=(-1/7)^2018-1:-6/7
Nguyễn Huy Thắng giải giúp mjnk bài này vs
tính tổng S=\(\left(\frac{-1}{7}\right)^0+\left(\frac{-1}{7}\right)^1+\left(\frac{-1}{7}\right)^2+...+\left(\frac{-1}{7}\right)^{2007}\)
S=(−1/7)^0+(−1/7)^1+(−1/7)^2+...+(−1/7)^2007
7S = 1+(−1/7)^1+(−1/7)^2+...+(−1/7)^2007
=> 7S = 7+(−1/7)^1+(−1/7)^2+...+(−1/7)^2006
=> 6S = 6-(−1/7)^2007
=> S= 1-(−1/7^2007/6)
\(\left(\frac{1}{2}+\frac{2015}{2016}+\frac{2016}{2017}+1\right)\left(\frac{2105}{2016}+\frac{2016}{2017}+\frac{7}{22}\right)-\left(\frac{1}{2}+\frac{2015}{2016}+\frac{2016}{2017}\right)\left(\frac{2015}{2016}+\frac{2016}{2017}+\frac{7}{22}+1\right)\)
Tính S = \(\left(\frac{-1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+.....+\left(-\frac{1}{7}\right)^{2016}\)
S= -(1/7^0 + 1/7^1+ 1/7^2 + 1/7^3 +...+ 1/7^2016)
Xét A = 1/7^0 + 1/7^1 + 1/7^2 + 1/7^3 +...+ 1/7^2016
=>7A= 7 + 1/7^0 + 1/7^1 + ...+ 1/7^2015
=> 6A = 7 - 1/7^2016
=> A = (7 - 1/7^2016)/6
=>S=-(7-1/7^2016)/6
Tính tổng: \(S=\left(\frac{1}{7}\right)^0+\left(\frac{1}{7}\right)^1+\left(\frac{1}{7}\right)^2+...+\left(\frac{1}{7}\right)^{2014}\)
tính tổng \(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^3+\left(-\frac{1}{7}\right)^4+.....+\left(-\frac{1}{7}\right)^{2007}\)
S=1-1/7-(1/7)^3-......-(1/7)^2017
49S=49-7-1/7-(1/7)^3-.,.....-(1/7)^2015
49S-S=48S=49-7-1-(1/7)^2017
48S=41-(1/7)^2017
S=41/48-(1/7)^2017/48
k nha
Tính \(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+\left(-\frac{1}{7}\right)^2+...\left(-\frac{1}{7}\right)^{2007}\)
các bạn giúp mình với !!!