Chứng minh 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 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
chứng tỏ 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, cho A = 9999931999 - 5555571997
Chứng minh rằng A chia hết cho 5
b, Chứng tỏ rằng :
\(\dfrac{1}{41}+\dfrac{1}{42}+\dfrac{1}{43}+....+\dfrac{1}{79}+\dfrac{1}{80}\) >\(\dfrac{7}{12}\)
A=1\41+1\42+1\43+...+1\79+1\80.chung minh A >7\12
1,Chứng minh rằng:
1/2<1/51+1/52+...+1/100<1
2,Chứng minh 1/41+1/42+1/43+...+1/79+1/80>7/12
