\(\frac{69}{157}-\left(2+\left(3+\left(4+5^{-1}\right)^{-1}\right)^{-1}\right)^{-1}\)

\(\frac{69}{157}-\left(2+\left(3+4+5^{-1}\right)^{-1}\left(^{-1}\right)\right)^{-1}\)

Tính hợp lý

\(\left(\frac{-1}{2}\right)-\left(\frac{-3}{5}\right)+\left(\frac{-1}{9}\right)+\frac{1}{127}-\left(+\frac{7}{18}\right)+\frac{4}{35}-\left(\frac{-2}{7}\right)\)

Giải chi tiết giúp mk bài này với:  Tính hợp lý  :

\(A=\left(-\frac{2}{9}\right)-\left(-\frac{1}{121}\right)+\left(-\frac{3}{5}\right)+\left(-\frac{1}{2}\right)-\left(-1\frac{13}{18}\right)-\frac{1}{7}-\frac{9}{35}\)

\(B=0,75+\frac{3}{5}+\left(\frac{2}{9}-1\frac{3}{5}+1\frac{1}{4}\right)\)

\(C=1-2+3-4+...+79-80\)

Tính hợp lý ( nếu có thể):

\(\left(1+\frac{1}{2}\right)\left(1+\frac{1}{3}\right)\left(1+\frac{1}{4}\right)...\left(1+\frac{1}{49}\right)\)

Tính hợp lý:

\(\left(-\frac{1}{2}\right)+\left(-\frac{3}{5}\right)+\left(-\frac{1}{9}\right)+\frac{1}{127}-\frac{7}{18}+\frac{4}{35}-\left(-\frac{2}{7}\right)\)

Tính hợp lý nếu có thể:

a) \(2\frac{1}{7}:\left(\frac{1}{15}-1\frac{2}{5}\right)-2\frac{1}{7}:\left(\frac{17}{15}+2\frac{1}{5}\right)\)

b) \(\left(\frac{-2}{3}\right)^{-4}.\left(-4\right)^2-\left[\left(\frac{7}{3}\right)^0\right]^{2016}-10\frac{1}{3}\)

thực hiện phép tính 1 cách hợp lý

\(B=1+\frac{1}{2}\left(1+2\right)+\frac{1}{3}\left(1+2+3\right)+\frac{1}{4}\left(1+2+3+4\right)+...+\frac{1}{20}\left(1+2+3+...+20\right)\)

tính hợp lý: 

a) \(\left(\frac{9}{10}-\frac{15}{16}\right)\left(\frac{5}{12}-\frac{11}{15}-\frac{7}{20}\right)\)

b) \(\left(\frac{1}{2}-1\right)\left(\frac{1}{3-1}\right)\left(\frac{1}{4}-1\right).......\left(\frac{1}{100}-1\right)\)