Tìm X
\(\frac{1}{2+4}\)+\(\frac{1}{2+4+6}\)+\(\frac{1}{2+4+6+8}\)+........+\(\frac{1}{2+4+6+8+.....+2xX}\)=\(\frac{503}{1007}\)
Ai trong vòng tối nay giải được trước 9 giờ 3 kick
So sánh:\(\frac{\frac{\frac{1}{2}}{\frac{3}{4}}}{\frac{\frac{5}{6}}{\frac{7}{8}}}+\frac{\frac{\frac{8}{7}}{\frac{6}{5}}}{\frac{\frac{4}{3}}{\frac{2}{1}}}\) và\(\frac{\frac{\frac{1}{2}}{\frac{3}{4}}+\frac{\frac{8}{7}}{\frac{6}{5}}}{\frac{\frac{5}{6}}{\frac{7}{8}}+\frac{\frac{4}{3}}{\frac{2}{1}}}\)và \(\frac{\frac{\frac{1}{2}+\frac{8}{7}}{\frac{3}{4}+\frac{6}{5}}}{\frac{\frac{5}{6}+\frac{4}{3}}{\frac{7}{8}+\frac{2}{1}}}\)và\(\frac{\frac{\frac{1+8}{2+7}}{\frac{3+6}{4+5}}}{\frac{5+4}{\frac{6+3}{2+1}}}\)
\(\frac{2\cdot x+1}{2}+\frac{4\cdot x+1}{4}+\frac{^{6\cdot x+1}}{6}=12\frac{11}{12}\)
TÍNH BẰNG CÁCH THUẬN TIỆN NHẤT
A)\(\frac{2}{3}\cdot\frac{4}{5}+\frac{1}{3}\cdot\frac{4}{5}=\)
B)\(\frac{1}{2}:\frac{3}{4}+\frac{1}{6}:\frac{3}{4}=\)
C)\(\frac{2}{3}\cdot\frac{4}{5}-\frac{1}{3}\cdot\frac{4}{5}=\)
D)\(\frac{1}{2}:\frac{3}{4}-\frac{1}{6}:\frac{3}{4}=\)
\(\frac{10+\frac{9}{2}+\frac{8}{3}+\frac{7}{4}+ \frac{6}{5}+\frac{5}{6}+\frac{4}{7}+\frac{3}{8}+\frac{2}{9}+\frac{1}{10}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{10}+\frac{1}{11}}\)
Tìm X
\(\frac{1}{2+4}\)+\(\frac{1}{2+4+6}\)+\(\frac{1}{2+4+6+8}\)+.........+\(\frac{1}{2+4+6+8+......+Xx2}\)
\(\frac{8}{1}+\frac{7}{2}+\frac{6}{3}+\frac{5}{4}+\frac{4}{5}+\frac{3}{6}+\frac{2}{7}+\frac{1}{8}\)
\(1:\frac{1}{2}:\frac{2}{3}:\frac{3}{4}:\frac{4}{5}:\frac{5}{6}:\frac{6}{7}:\frac{7}{8}=........\)
bài 1
\(\frac{18}{11}+\left(\frac{7}{4}-\frac{3}{5}\right):\frac{1}{2}\)
\(\frac{8}{5}-\frac{1}{2}:\frac{1}{4}\cdot\left(\frac{3}{7}+\frac{1}{4}\right)\)
\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+\frac{1}{30}+\frac{1}{42}\)