\(2\frac{3}{13}\cdot5\frac{4}{5}\cdot7\frac{6}{7}:\frac{2}{8}=\frac{29}{13}\cdot\frac{29}{5}\cdot\frac{55}{7}:\frac{2}{8}=\frac{29\cdot29\cdot55\cdot8}{13\cdot5\cdot7\cdot2}=\frac{29\cdot29\cdot11\cdot4}{13\cdot1\cdot7\cdot1}=\frac{37004}{91}\)
Chúc bạn học tốt!^_^
tính :\(\frac{1}{1\times2\times3}+\frac{1}{2\times3\times4}+\frac{1}{3\times4\times5}+\frac{1}{4\times5\times6}+\frac{1}{5\times6\times7}+\frac{1}{6\times7\times8}+\frac{1}{7\times8\times9}+\frac{1}{8\times9\times10}\)
TÍNH NHANH:\(\frac{1}{1\times3\times5}+\frac{1}{2\times5\times8}+\frac{1}{3\times5\times7}+\frac{1}{5\times8\times11}+\frac{1}{5\times7\times9}+\frac{1}{8\times11\times14}+...+\frac{1}{995\times997\times999}+\frac{1}{1493\times1496\times1499}\)
Tính nhanh
\(\frac{2}{1\times3}+\frac{2}{3\times5}+\frac{2}{5\times7}+\frac{2}{7\times9}+\frac{2}{9\times11}\)
\(\left(\frac{4}{1\times3}+\frac{4}{3\times5}+\frac{4}{5\times7}+\frac{4}{7\times9}\right)\times10-x=0\)
a,tìm x :( 1/2- 1/3 - 1/6 ) x (1/2 + 2/3 + 3/4 +4/5 + .......+ 2019 /2020 ) + 3/4 : x = 9/10
b,\(X+\left(\frac{3}{1\times3}+\frac{3}{3\times5}+\frac{3}{5\times7}+....+\frac{3}{13\times15}\right)=2\frac{1}{5}\)\(2\frac{1}{5}\)
MK ĐANG CẦN RẤT GẤP BẠN NÀO NHANH MK TICK CHO NHỚ LÀ PHẢI CÓ CÁCH GIẢI NHÉ!
\(\left(\frac{1}{1\times3}+\frac{1}{3\times5}+\frac{1}{5\times7}+\frac{1}{7\times9}+\frac{1}{9\times11}\right)\times y=\frac{2}{3}\)
Tìm y
\(\frac{4}{1\times3}+\frac{4}{3\times5}+\frac{4}{5\times7}+...+\frac{4}{11\times13}=?\)
Tính \(\frac{2}{1\times3}+\frac{2}{3\times5}+\frac{2}{5\times7}+...+\frac{2}{77\times79}\)
Tính nhanh:
a) \(\frac{1}{2}\)+\(\frac{1}{2\times3}\)+\(\frac{1}{3\times4}\)+\(\frac{1}{4\times5}\)+\(\frac{1}{5\times6}\)+\(\frac{1}{6\times7}\)+\(\frac{1}{7}\)\(\times\)\(\frac{1}{8}\)
b) \(\frac{1996\times1995-996}{1000+1996\times1994}\)
