Question

C = \(\frac{3}{1.3}+\frac{3}{3.5}+\frac{3}{5.7}+...+\frac{3}{99.101}\)

Answer 1

\(C=\frac{3}{1.3}+\frac{3}{3.5}+\frac{3}{5.7}+...+\frac{3}{99.101}\)

\(=\frac{1}{1}-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-...-\frac{1}{99}+\frac{1}{99}-\frac{1}{101}\)

\(=\frac{1}{1}-\frac{1}{101}\)

\(=\frac{100}{101}\)

Answer 2

\(C=\frac{3}{2}\left(1-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+......+\frac{1}{99}-\frac{1}{101}\right)\)

\(C=\frac{3}{2}\left(1-\frac{1}{101}\right)\)

\(C=\frac{3}{2}.\frac{100}{101}=\frac{150}{101}\)

Answer 3

C = 31.3+33.5+35.7+...+399.101

C = 3\(\left(\frac{1}{1.3}+\frac{1}{3.5}+\frac{1}{5.7}+...+\frac{1}{99.101}\right)\)

 

 

C =3\(\left(\frac{1}{1}-\frac{1}{3}+\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+...+\frac{1}{99}-\frac{1}{101}\right)\)

C =3\(\left(1-\frac{1}{101}\right)\)

C=3 . \(\frac{100}{101}\)

C=\(\frac{300}{101}\)

Answer 4

chữ C= đầu tiên là đề đó nha

Answer 5

\(\frac{100}{101}\)