Question

tính :

S = 2/3.5 + 3/5.8 + 11/8.19 + 13/19.32 + 25/32.57 + 30/57-87

làm nhanh giúp ạ

 

Answer 1

\(S=\frac{2}{3.5}+\frac{3}{5.8}+\frac{11}{8.19}+\frac{13}{19.32}+\frac{25}{32.57}+\frac{30}{57.85}\)

\(S=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{8}+\frac{1}{8}-\frac{1}{19}+\frac{1}{19}-\frac{1}{32}+\frac{1}{32}-\frac{1}{57}+\frac{1}{57}-\frac{1}{87}\)

\(S=\frac{1}{3}-\frac{1}{87}\)

\(S=\frac{28}{87}\)