CMR
100-(1/2+1/3+1/4+...+1/100)=2/3+3/4+...+99/100
thuận tiện 19/20x2/100+19/20x2/100
75/76x102/100-75/76x2/100
3x7/10+7/10x5+2x7/10
giá trị biểu thức
2/5+2/3x3/4
1/2x1/3-1/8
(1/2+1/3):3/9
tính nhanh \(\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{100}}{\frac{1}{2}+\frac{2}{3}+\frac{3}{4}+....+\frac{99}{100}}\)
A = 1-2+3-4+5-6+.....+97-98+99-100+101
B = 1+2-3-4+5+6-7-8+......+98-99-100+101
Tính nhanh
a. 5/11 + 1/4 + 2/5 + 6/11 + 3/4 + 6/25 + 9/25
b. 19/4 + 37/100 + 1/8 + 1/2 + 163/100 + 3/8
(1-1/2)×(1-2/3)×(1-3/4)×......×(1-99/100
tính tổng :S = 1/1*2 + 1/2*3 + 1/3*4 + 1/4*5 + .........+ 1/99*100
1+2+3+4+5+6+....+100: 100=???????????
2. Tính: A) 2/3 + 5/6 + 1/18. B) 3/4 + 2/25 + 7/100. C) 1/12 + 1/6 + 3/4.
1+1/2+2+2/3+3+3/4+...+99+99/100