\(S=\left(\frac{-1}{7}\right)^0+\left(\frac{-1}{7}\right)^1+...........+\left(\frac{-1}{7}\right)^{2007}\)
\(\Rightarrow\frac{-1}{7}S=\left(\frac{-1}{7}\right)^1+\left(\frac{-1}{7}\right)^2+........+\left(\frac{-1}{7}\right)^{2008}\)
\(\Rightarrow\frac{-1}{7}S-S=\frac{-8}{7}S=\left(\frac{-1}{7}\right)^{2008}-\left(\frac{-1}{7}\right)^0\)
\(\Rightarrow S=\frac{\left(\frac{-1}{7}\right)^{2008}-1}{\frac{-8}{7}}\)
Tính tổng A = (\(\frac{1}{7}\))0 + (\(\frac{1}{7}\))1 + ... + ( \(\frac{1}{7}\))2007
tính tổng S=(-1/7)^0+(-1/7)^1+....+(-1/7)^2007
tính tổng S =(-1/7)^0+(-1/7)^1+....+(-1/7)^2007
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 \(\frac{7}{8}\)
tinh S=1/2+(1/2)^2+....+(1/2)^99
tinh B=(-1/7)^0+(-1/7)^2+...+(-1/7)^2007
tính:\(S=\left(-\frac{1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+...+\left(-\frac{1}{7}\right)^{2007}\)
tính S=\(\left(\frac{-1}{7}\right)^0+\left(-\frac{1}{7}\right)^1+...+\left(-\frac{1}{7}\right)^{2007}\)
tổng Stính =(-1/7)^0+(-1/7)^1+....+(-1/7)^2007
7a) Tính tổng :
\(A=\left(-7\right)+\left(-7\right)^2+...+\left(-7\right)^{2006}+\left(-7\right)^{2007}\)
Chứng minh A chia hết cho 43
