Question

\(\frac{1}{3\cdot4}+\frac{1}{4\cdot6}+\frac{1}{6\cdot9}+\frac{1}{9\cdot13}+\frac{1}{13\cdot18}=...\)

Nhập kết quả dưới dạng phân số tối giản

Answer 1

= \(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{6}+\frac{1}{6}-\frac{1}{9}+\frac{1}{9}-\frac{1}{13}+\frac{1}{13}-\frac{1}{18}\)\(\frac{1}{18}\)

= \(\frac{1}{3}-\frac{1}{18}\)

= \(\frac{5}{18}\)

Answer 2

kết quả là 439/2808

Answer 3

[{1/4-1/4}+ { 1/6-1/6}+{1/9-1/9}+{1/13-1/13}]*11/4=0

Answer 4

\(\frac{1}{3.4}+\frac{1}{4.6}+\frac{1}{6.9}+\frac{1}{9.13}+\frac{1}{13.18}\)

=\(\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{6}+\frac{1}{6}-\frac{1}{9}+\frac{1}{9}-\frac{1}{13}+\frac{1}{13}-\frac{1}{18}\)

=\(\frac{1}{3}-\frac{1}{18}=\frac{6}{18}-\frac{1}{18}=\frac{5}{18}\)

bạn kick cho mình nhé!