câu hỏi tương tự nha bạn

tick cho mk nha bạn

b)\(B=\dfrac{3}{2}+\dfrac{13}{12}+\dfrac{31}{30}+...+\dfrac{9901}{9900}\)

\(=1+\dfrac{1}{2}+1+\dfrac{1}{12}+1+\dfrac{1}{30}+...+1+\dfrac{1}{9900}\)

\(=1+1+1+...+1\left(50cs\right)+\dfrac{1}{2}+\dfrac{1}{12}+...+\dfrac{1}{9900}\)

\(=50+\dfrac{1}{2}+\dfrac{1}{12}+\dfrac{1}{30}+...+\dfrac{1}{9900}\)

\(C=\dfrac{5}{6}+\dfrac{19}{20}+\dfrac{41}{42}+...+\dfrac{10099}{10100}\)

\(=\left(1-\dfrac{1}{6}\right)+\left(1-\dfrac{1}{20}\right)+\left(1-\dfrac{1}{42}\right)+...+\left(1-\dfrac{1}{10100}\right)\)

\(=1+1+...+1\left(50cs\right)-\dfrac{1}{6}-\dfrac{1}{20}-\dfrac{1}{42}-...-\dfrac{1}{10100}\)

\(B-C=\left(50+\dfrac{1}{2}+\dfrac{1}{12}+...+\dfrac{1}{9900}\right)-\left(50-\dfrac{1}{6}-\dfrac{1}{20}-...-\dfrac{1}{10100}\right)\)

\(=\dfrac{1}{2}+\dfrac{1}{6}+\dfrac{1}{12}+...+\dfrac{1}{9900}+\dfrac{1}{10100}\)

\(=\dfrac{1}{1.2}+\dfrac{1}{2.3}+\dfrac{1}{3.4}+...+\dfrac{1}{100.101}\)

\(=1-\dfrac{1}{2}+\dfrac{1}{2}-\dfrac{1}{3}+\dfrac{1}{3}-\dfrac{1}{4}+\dfrac{1}{4}-...+\dfrac{1}{100}-\dfrac{1}{101}\)

\(=1-\dfrac{1}{101}=\dfrac{100}{101}\)

Chúc Bạn Học Tốt và Đạt nhiều thành tích tốt !!!

a. Sắp xếp:

\(-\dfrac{7}{9};\dfrac{-40}{-50};\dfrac{27}{33};\dfrac{-6}{-4}\)

b. Sắp xếp:

\(-\dfrac{14}{37};-\dfrac{14}{33};0;\dfrac{18}{19};\dfrac{17}{20};\dfrac{4}{3}\)

Có j sai thì ns vs mk nha! Đúng thì tick nha! Chúc bn học tốt!

Thanks nha

\(a,\dfrac{3}{5}+\dfrac{1}{5}.\dfrac{-17}{9}=\dfrac{3}{5}-\dfrac{17}{45}=\dfrac{27}{45}-\dfrac{17}{45}=\dfrac{10}{45}=\dfrac{2}{9}\\ b,\left(-\dfrac{4}{15}-\dfrac{18}{19}\right)-\left(\dfrac{20}{19}+\dfrac{11}{15}\right)=-\dfrac{4}{15}-\dfrac{18}{19}-\dfrac{20}{19}-\dfrac{11}{15}=\left(-\dfrac{4}{15}-\dfrac{11}{15}\right)-\left(\dfrac{18}{19}+\dfrac{20}{19}\right)=-1-2=-3\)

\(a,=\dfrac{3}{5}+\left(-\dfrac{17}{45}\right)=\dfrac{2}{9}\)

\(b,=-\dfrac{4}{15}-\dfrac{18}{19}-\dfrac{20}{19}-\dfrac{11}{15}=-3\)

a.2/9
b.-3

a.2/9 b.(-3)