Ta có: \(\left(\dfrac{1}{1\cdot2}+\dfrac{1}{2\cdot3}+\dfrac{1}{3\cdot4}+...+\dfrac{1}{8\cdot9}\right)\cdot x=\dfrac{23}{45}\)
\(\Leftrightarrow x\left(1-\dfrac{1}{9}\right)=\dfrac{23}{45}\)
\(\Leftrightarrow x=\dfrac{23}{45}\cdot\dfrac{9}{8}=\dfrac{23}{40}\)
(1/1.2 +1/2.3 1/3.4 + ....+1/8.9) x=23/45
(1/1.2+1/2.3+1/3.4+.....+1/8.9+1/9.10).100-[5/2:(x+206/100):1/2=89
tìm x
(1/1.2+1/2.3+1/3.4+....+1/8.9+1/9.10).100-[5/2:(x+206/100)]:1/2=89
tìm x hộ mình với
A= 1/1.2 + 1/2.3 + 1/3.4 + 1/4.5 + 1/5.6 + 1/6.7 + 1/ 7.8 + 1/ 8.9 + 1/ 9.10
1/1.2+1/2.3+1/3.4+1/4.5+1/5.6+1/6.7+1/7.8+1/8.9+1/9.10
Làm nhanh giùm mình với ạ,càng chi tiết càng tốt ạ
Tính nhanh:
B= 1/1.2 + 1/2.3 + 1/3.4 + ... + 1/8.9 + 1/9.10
Lưu ý: các bạn nhớ ghi rõ cách làm nhé
MƠN NHÌU
Tinh
A= 1/1.2+1/2.3+1/3.4+1/4.5+1/5.6+1/6.7+1/7.8+1/8.9+1/.910+1/10.11+1/12.13
co loi giai ha
Tính nhanh tổng sau:
D=1/1.2+1/2.3+1/3.4+...+1/8.9+1/99.100
Chứng minh rằng:
\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}+\frac{1}{7.8}+\frac{1}{8.9}+\frac{1}{9.10}\)
