(1-1/10)x(1-1/11)x(1-1/12)x(1-1x1/13)=\(\dfrac{9}{10}\)x\(\dfrac{10}{11}\)x\(\dfrac{11}{12}\)x\(\dfrac{12}{13}\)=\(\dfrac{9}{13}\).
Tính nhanh:
A = 1/10 + -1/11 + 1/12 + -1/13 + 1/14 + -1/15 + 1/16 +1/15 + -1/14 + 1/13 + -1/12 + 1/11 + -1/10
1/10×11+1/11×12+1/12×13+...1/49×50
a) 1/7+1/8+1/9+1/10+1/11+1/12+1/13+1/14+1/15+1/18+1/22+1/24+1/28+1/33
cho a = 1/10+1/11+1/12+1/13+1/14
hoi a co phai la so tu nh hay khong
ien
4, tính nhanh
5và 1/2+6 và 11/12 +9 và 2/13
(1-3/4)x(1-3/7x(1-3/10)x(1-3/13)x....x(1-3/13)x1- (3/100)
ai nhanh 10 tick
1/2004×(1-1/2005)×(1_1/2006)×(1-1/2007)-(1-1/2008)
a, 13/19 + 1 - 15/19 - 4/19
b, 3/5 +6/11 +7/13 +2/5 +16/11 +19/13
c, 1/3 +1/6 + 1/12 +1/24 +1/48
d, 1/2 +1/6 +1/12 +1/20 +1/30 +1/42
tính nhanh:
A=3/34 x 10 1/12 x 8/9 x 2 1/8 x 3/13 x 26/37 x 1 9/11 x 3/4
Bài 1: Tìm x biết: 10+ 11+ 12+ 13+...+ x = 5106
