1(\(\left(\frac{4}{286}-\frac{2}{7\times9}\right)\left(\frac{4}{286}-\frac{2}{9\times11}\right)......\left(\frac{4}{286}-\frac{2}{97\times99}\right)\)
2)\(A=\frac{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+...+\frac{1}{19}+\frac{1}{20}}{\frac{19}{1}+\frac{18}{2}+\frac{17}{3}+...+\frac{2}{18}+\frac{1}{19}}\)