CHo `M` `=` \(\dfrac{\left(\dfrac{3}{1\cdot4}+\dfrac{3}{2\cdot6}+\dfrac{3}{3\cdot8}+\dfrac{3}{4\cdot10}+...+\dfrac{3}{49\cdot100}\right)}{\left(1-\dfrac{1}{4}\right)\left(1-\dfrac{1}{5}\right)\left(1-\dfrac{1}{6}\right)\cdot\cdot\cdot\left(1-\dfrac{1}{100}\right)}\)
Chứng `M` có giá trị là 1 số nguyên
Hép - mi - pờ - li
a) \(\dfrac{1}{2}\cdot\dfrac{-3}{4}\cdot\dfrac{-5}{8}\cdot\dfrac{-8}{9}\)
b) \(\left(\dfrac{2}{1\cdot3}+\dfrac{2}{3\cdot5}+\dfrac{2}{5\cdot7}\right)\cdot\left(\dfrac{10\cdot13}{3}-\dfrac{2^2}{3}-\dfrac{5^3}{3}\right)\)
câu này làm cx đc hoặc ko làm cx ko sao :)
\(\dfrac{8}{9}+\dfrac{1}{9}\cdot\dfrac{2}{9}+\dfrac{1}{9}\cdot\dfrac{7}{9}\)
Tính tổng:
\(\left(1+\dfrac{1}{1\cdot3}\right)\cdot\left(1+\dfrac{1}{2\cdot4}\right)\cdot\left(1+\dfrac{1}{3\cdot5}\right)\cdot...\cdot\left(1+\dfrac{1}{2019\cdot2021}\right)\)
\(\left(\dfrac{1}{2}+1\right).\left(\dfrac{1}{3}+1\right).\left(\dfrac{1}{4}+1\right).\cdot\cdot\cdot.\left(\dfrac{1}{99}+1\right)\) làm ơn giúp mình với
\(\dfrac{1}{2}\cdot x+\dfrac{3}{5}\cdot\left(x-2\right)=3\)
Ai giúp với
\(\left(\dfrac{2}{3}x-\dfrac{1}{2}\right)\cdot\dfrac{3}{4}-\dfrac{2}{5}x=4\dfrac{1}{4}\)
giải đầy đủ nhé
a)\(\dfrac{8}{5}\cdot\dfrac{2}{3}+\dfrac{-5\cdot5}{3\cdot5}\)
b) \(\dfrac{6}{7}+\dfrac{5}{8}:5-\dfrac{3}{16}\left(-2\right)^2\)
\(\left(\dfrac{1}{5}x-\dfrac{4}{5}\right)\cdot\left(x+\dfrac{1}{4}\right)=0\)
\(2\cdot\left(\dfrac{1}{2}x-\dfrac{1}{3}\right)=\dfrac{1}{4}\)