Chứng tỏ rằng: 

1/1945² + 1/1946² + 1/1947² + .......+1/1974² + 1/1975² < 1/1944

m.n ơi cho em hỏi zới !!!!

Chứng minh răng : 

1/1945^2+1/1946^2+1/1947^2+.....+1/1974^2+1/1975^2<1/1944

M= 1/1975*(2+1/1945-1)-1/1945*(1-2/1975)-1974/1975*1946/1945-3/1975*1945

Chứng tỏ rằng

\(\frac{1}{1945^2}\)\(+\frac{1}{1946^2}+\frac{1}{1947^2}+...+\frac{1}{1974^2}+\frac{1}{1975^2}\)<1/1944

\(M=\frac{1}{1975}.\left(\frac{2}{1975}-1\right)-\frac{1}{1945}.\left(1-\frac{2}{1975}\right)-\frac{1974}{1975}.\frac{1946}{1945}-\frac{3}{1975.1945}\)

Tính M=\(\dfrac{1}{1975}\left(\dfrac{2}{1945}-1\right)-\dfrac{1}{1945}\left(1-\dfrac{2}{1975}\right)+\dfrac{1974}{1975}\times\dfrac{1946}{1945}-\dfrac{3}{1975\times1945}\)

Tính nhanh:

A = \(\dfrac{1}{1975}\left(\dfrac{2}{1975}-1\right)+\left(1-\dfrac{2}{1945}\right)+\dfrac{1974}{1975}.\dfrac{1945}{1946}\)

Tính Q = \(\dfrac{1}{1275}.\left(\dfrac{x}{1945}-1\right)-\dfrac{1}{1945}.\left(1-\dfrac{x}{1975}\right)-\dfrac{1974}{1975}.\dfrac{1946}{1945}-\dfrac{3}{1975.1945}\)

Tính giá trị biểu thức

\(M=\frac{1}{1975}.\left(\frac{2}{1975}-1\right)-\frac{1}{1945}.\left(1-\frac{2}{1975}\right)-\frac{1974}{1975}.\frac{1946}{1945}-\frac{3}{1975.1945}\)