a,2/5.7 + 2/7.9 + 2/9.11 + ... + 2/53.55
b,1/2 .1/3 +1/4 . 1/5 + ... + 1/8 . 1/9
c,(1+1/2)(1+1/3)(1=1/4).....(1+1/99)
S= 2/5.7 + 2/7.9 + 2/9.11 + .... + 2/93.95 + 3/95.98 + 4/98.102 + 5/102.107 + 2012/107.2119
Mình cần gấp lắm ! Trước 8h mình phải nộp bài cho cô giáo rồi. Giúp mình nha thanks
\(\dfrac{2}{3.5}+\dfrac{2}{5.7}\dfrac{2}{7.9}+.........+\dfrac{2}{99.101}\)
\(P=\dfrac{2}{3.5}+\dfrac{2}{5.7}+\dfrac{2}{7.9}+\dfrac{2}{9.11}+\dfrac{2}{11.13}+\dfrac{2}{13.15}\)
Tính:
a) M=2/3.5+2/5.7+2/7.9+...+2/97.99
b) N=3/5.7+3/7.9+3/9.11+...+3/197.199
Thực hiện phép tính:
J) \(\dfrac{2}{5.7}+\dfrac{2}{7.9}+...+\dfrac{2}{53.55}\)
tính tổng S=2/1.3+2/3.5+2/5.7+2/7.9+2/9.11
Tinh nhanh:
S = 2/5.7 + 2/7.9+ 2/9.11+...+2/93.95
4/5.7+4/7.9+4/9.11+...+4/53.55 = ?
a) M = 2/3.5 + 2/5.7 + 2/7.9 + ... + 2/97.99
b) N = 3/5.7 + 3/7.9 + 3/9.11 + ... + 3/197.199
c) P = 1/1.2 + 2/2.4 + 3/4.7 + ... + 10/46.56