A= 2x3/3x60x63+2x3/3x63x66+...+2x3/3x117x120+2/2007
=2/3(1/60-1/63+1/63-1/66+...+1/117-1/120)+2/2007
=2/3(1/60-1/120)+2/2007=1/180+2/2007
Lam tuong tu nhu vay vs B. B nhan ca tu va mau cho 4 sua do thu 5/4 ra ngoai. Cuoi cung tinh dk A<B
So sánh
A=\(\frac{2}{60.63}+\frac{2}{63.66}+...+\frac{2}{117.120}+\frac{2}{2003}\)
và B=\(\frac{5}{40.44}+\frac{5}{44.48}+...+\frac{5}{76.80}+\frac{5}{2003}\)
So sánh
A=\(\frac{2}{60.63}+\frac{2}{63.66}+...+\frac{2}{117.120}+\frac{2}{2003}\)
và B=\(\frac{5}{40.44}+\frac{5}{44.48}+...+\frac{5}{76.80}+\frac{5}{2003}\)
So sánh
C=\(\frac{2}{60.63}+\frac{2}{63.66}+...+\frac{2}{117.120}+\frac{2}{2006}\)
Và D=\(\frac{5}{40.44}+\frac{5}{44.48}+...+\frac{5}{76.80}+\frac{5}{2006}\)
So sánh
A=\(\frac{2}{60.63}+\frac{2}{63.66}+..+\frac{2}{117.120}+\frac{2}{2003}\)
B=\(\frac{5}{40.44}+\frac{5}{44.48}+..+\frac{5}{76.80}+\frac{5}{2003}\)
So sánh \(A=\frac{2}{60.63}+\frac{2}{63.66}+...+\frac{2}{117.120}+\frac{2}{2006}\)và \(B=\frac{5}{40.44}+\frac{5}{44.48}+...+\frac{5}{76.80}+\frac{5}{2006}\)
So sánh:
\(A=\dfrac{2}{60.63}+\dfrac{2}{63.66}+.........+\dfrac{2}{117.120}+\dfrac{2}{2003}\)
và \(B=\dfrac{5}{40.44}+\dfrac{5}{44.48}+........+\dfrac{5}{76.08}+\dfrac{5}{2003}\)
so sánh 2 số A và B nếu
\(A=-\frac{1}{2018}-\frac{3}{2017^2}-\frac{5}{2017^3}-\frac{7}{2017^4};B=\frac{-1}{2018}-\frac{7}{2017^2}-\frac{5}{2017^3}-\frac{3}{2017^4}\)
So sánh A và B nếu
\(A=\frac{-1}{2018}-\frac{3}{2017^2}-\frac{5}{2017^3}-\frac{7}{2017^4}\)
\(B=\frac{-1}{2018}-\frac{7}{2017^2}-\frac{5}{2017^3}-\frac{3}{2017^4}\)
So sánh:
A= 2/60.63+2/63.66+....+2/117.120+2/2003
B=5/40.44+5/44.48+...+5/76.80+5/2003
Làm hộ mình nha !
