CMR 1/41+1/42+1/43+...+1/79+7/80 <7/12
chứng tỏ 1/41+1/42+1/43+.......+1/79+1/80>7/12
Cm: \(\frac{1}{41}+\frac{1}{42}+\frac{1}{43}+...+\frac{1}{79}+\frac{1}{80}>\frac{7}{12}\)
Cmr 1/41+4/42+4/43+.........+1/79+1/80>7/12
Chứng tỏ rằng: 1/41+1/42+1/43+...+1/79+1/80>7/12
Chứng minh rằng: 1/41+1/42+1/43+..........+1/79+1/80>7/12
chứng tỏ rằng :1 /41 +1/42 +1/43 +...+1/79+1/80 >7/12
A=1\41+1\42+1\43+...+1\79+1\80.chung minh A >7\12
Chững minh rằng : 1/41 + 1/42 + 1/43 +... + 1/79 + 1/80 > 7/12