F=(1-1/6)+(1-2/7)+(1-3/8)+...+(1-88/ 93)
\(C=\dfrac{88-\dfrac{1}{6}-\dfrac{2}{7}-\dfrac{3}{8}-...-\dfrac{88}{93}}{-\dfrac{1}{12}-\dfrac{1}{14}-\dfrac{1}{16}...\dfrac{1}{186}}\)
tính C
C = ( 88 - 1/6 - 2/7 - 3/8 - ... - 88/93 ) / ( -1/12 - 1/14 - 1/16 - ... - 1/186 )
D = 1 - 5/6 + 7/12 - 9/20 + 11/30 - 13/42 + 15/56 - 17/12 + 19/90
các cou ui zải zúp mk bài này nhé:333
mk hứa sẽ chấm đúng:))
trâng trọn cảng ơm ^-^
\(\dfrac{\left(1-\dfrac{1}{6}\right)+\left(1-\dfrac{2}{7}\right)+\left(1-\dfrac{3}{8}\right)+...+\left(1-\dfrac{88}{93}\right)}{\dfrac{-1}{12}-\dfrac{1}{14}-\dfrac{1}{16}-...-\dfrac{1}{186}}\)
\(\dfrac{\left(1-\dfrac{1}{6}\right)+\left(1-\dfrac{2}{7}\right)+\left(1-\dfrac{3}{8}\right)+...+\left(1-\dfrac{88}{93}\right)}{\dfrac{-1}{12}-\dfrac{1}{14}-\dfrac{1}{16}-...-\dfrac{1}{186}}\)
Rút gọn:
\(A=\left(1-\dfrac{1}{6}\right)+\left(1-\dfrac{2}{7}\right)+...+\left(1-\dfrac{88}{93}\right)\)
88-\(\frac{1}{6}\)-\(\frac{2}{7}\)-\(\frac{3}{8}\)-.......-\(\frac{88}{93}\)
-\(\frac{1}{12}\)-\(\frac{1}{14}\)-\(\frac{1}{16}\)-......-\(\frac{1}{186}\)
giải theo cách hợp lí
1-2=8-7-9-9-9-98-8-88--88-8-8-8-88-88-8-8--8--8-8-8-8--8-8-8
3+8+13+...+83+88+93+98+100=???