B=(\(\frac{5}{5}-\frac{1}{5}\)).(\(\frac{6}{6}-\frac{1}{6}\)).(\(\frac{7}{7}-\frac{1}{7}\))....(\(\frac{2019}{2019}-\frac{1}{2019}\))
=\(\frac{4}{5}.\frac{5}{6}.\frac{6}{7}....\frac{2018}{2019}\)
=\(\frac{4}{2019}\)
1.thực hiện phép tính
a.\(25.\left(\frac{-1}{5}\right)^3+\frac{1}{5}-2.\left(\frac{-1}{2}\right)^2-\frac{1}{2}\)
b.\(35^1_6:\left(\frac{-4}{5}\right)-46^1_6:\left(\frac{-4}{5}\right)\)
c.\(\left(\frac{-3}{4}+\frac{2}{5}\right):\frac{3}{7}+\left(\frac{3}{5}+\frac{-1}{4}\right):\frac{3}{7}\)
d.\(\frac{7}{8}:\left(\frac{2}{9}-\frac{1}{18}\right)+\frac{7}{8}.\left(\frac{1}{36}-\frac{5}{12}\right)\)
e.\(\frac{1}{6}+\frac{5}{6}.\frac{3}{2}-\frac{3}{2}+1\)
f.\(\left(-0,75-\frac{1}{4}\right):\left(-5\right)+\frac{1}{15}-\left(\frac{-1}{5}\right):\left(-3\right)\)
Bài 1: Thực hiện phép tính: (Tính nhanh nếu có thể)
a) \(\frac{-1}{24}-\left[\frac{1}{4}-\left(\frac{1}{2}-\frac{7}{8}\right)\right]\)
b) \(\left(\frac{5}{7}-\frac{7}{5}\right)-\left[\frac{1}{2}-\left(-\frac{2}{7}-\frac{1}{10}\right)\right]\)
c) \(\left(-\frac{1}{2}\right)-\left(-\frac{3}{5}\right)+\left(-\frac{1}{9}\right)+\frac{1}{17}-\left(-\frac{2}{7}\right)+\frac{4}{35}-\frac{7}{18}\)
Mọi người ơi, giúp mk với!!!
B1 : Tìm GTNN :
\(\left(x+2020\right)^4+\left|y-2019\right|-2018\)
B2 : Tính :
\(P=1+\frac{1}{2}.\left(1+2\right)+\frac{1}{3}.\left(1+2+3\right)+\frac{1}{4}.\left(1+2+3+4\right)+...+\frac{1}{2019}.\left(1+2+3+...+2019\right)\)
A=\(\left(3\frac{1}{3}+2,5\right):\left(3\frac{1}{6}-4\frac{1}{5}\right)-\frac{11}{31}\)
B=\(\left(-6\right).10:\left[-0,25+\frac{1}{2}:\left(-2\right)\right]+1\frac{3}{4}\)
Tính B=\(2020.\left(\frac{1}{2}-1\right).\left(\frac{1}{3}-1\right).....\left(\frac{1}{2019}-1\right)\left(\frac{1}{2020}-1\right)\)
\(\frac{0,8:\left(\frac{4}{5}.1,25\right)}{0,64-\frac{1}{25}}+\frac{\left(1,08-\frac{2}{25}\right):\frac{4}{7}}{\left(6\frac{5}{9}-3\frac{1}{4}\right).2\frac{2}{17}}+\left(1,2.0,5\right):\frac{4}{5}\)
\(\frac{\left(13\frac{1}{4}-2\frac{5}{27}-10\frac{5}{6}\right).230\frac{1}{25}+46\frac{3}{4}}{\left(1\frac{3}{7}+\frac{10}{3}\right):\left(12\frac{1}{3}-14\frac{2}{7}\right)}\)
Bài 31 : Tính :
a) \(\left(2^{-1}+3^{-1}\right):\left(2^{-1}-3^{-1}\right)+\left(2^{-1}.2^0\right):2^3\)
b) \(\left(-\frac{1}{3}\right)^{-1}-\left(-\frac{6}{7}\right)^0+\left(\frac{1}{2}\right)^2:2\)
c) \(\text{[}\left(0,1\right)^2\text{]}^0+\text{[}\left(\frac{1}{7}\right)^1\text{]}^2.\frac{1}{49}.\text{[}\left(2^3\right)^3:2^5\text{]}\)
Mong các cao nhân giúp ak , đang cần gấp
Tính nhanh :
\(B=\left(-\frac{1}{2}\right)-\left(-\frac{3}{5}\right)+\left(-\frac{1}{9}\right)+\frac{1}{131}-\left(-\frac{2}{7}\right)+\frac{4}{35}-\frac{7}{18}\)
