Question

1/1*2 + 1/2*3 + 1/3*4 + 1/4*5 + 1/5*6 + 1/6*7

Answer 1

\(\frac{1}{1.2}+\frac{1}{2.3}+\frac{1}{3.4}+\frac{1}{4.5}+\frac{1}{5.6}+\frac{1}{6.7}=1-\frac{1}{2}+\frac{1}{2}-\frac{1}{3}+...+\frac{1}{6}-\frac{1}{7}=1-\frac{1}{7}=\frac{6}{7}\)

tick đúng cho mình nha

Answer 2

1/1x2 + 1/2x3 + 1/3x4 + 1/4x5 + 1/5x6 + 1/6x7

= 1/1 - 1/2 + 1/2 - 1/3+ 1/3 - 1/4+...+ 1/6 - 1/7

= 1/1 - 1/7

= 6/7