\(a)\dfrac{-3}{26}+2\dfrac{4}{69}\)
\(=\) \(\dfrac{-3}{26}\) + \(\dfrac{142}{69}\)
\(=\) \(\dfrac{-207}{1794}\) + \(\dfrac{3692}{1794}\)
\(=\) \(\dfrac{\left(-207\right)+3692}{1794}\)
\(=\) \(1,942586399\)
8) \(\dfrac{17}{-26}.\left(\dfrac{1}{6}-\dfrac{5}{3}\right):\dfrac{17}{13}-\dfrac{20}{3}.\left(\dfrac{2}{5}-\dfrac{1}{4}\right)+\dfrac{2}{3}.\left(\dfrac{6}{5}-\dfrac{9}{2}\right)\)
TÍNH NHANH
a) \(\dfrac{11}{125}-\dfrac{17}{18}-\dfrac{5}{7}+\dfrac{4}{9}+\dfrac{17}{4}\)
b) \(1-\dfrac{1}{2}+2-\dfrac{2}{3}+3-\dfrac{3}{4}+4-\dfrac{1}{4}-3-\dfrac{1}{3}-2-\dfrac{1}{2}-1\)
c) \(26:\left\{{}\begin{matrix}\\\end{matrix}\right.\dfrac{3:\left(0,2-0,1\right)}{2,5.\left(0,8+1,2\right)}+\dfrac{\left(34,06-33,81\right).4}{6,84:\left(28,57-25,15\right)}+\dfrac{2}{3}:\dfrac{4}{21}\)
Các bạn ơi câu c là tới phân số ... 4/...15 là đóng ngoặc nhé. Hai ps đó trong ngoặc đấy
Thực hiện phép tính (tính nhanh nếu có thể):
a) \(\left(\dfrac{1}{2}-\dfrac{1}{3}\right)-\left(\dfrac{5}{3}-\dfrac{3}{2}\right)+\left(\dfrac{7}{3}-\dfrac{5}{2}\right)\)
b) \(\left(\dfrac{3}{4}-1\dfrac{1}{6}\right)^2:\sqrt{\dfrac{25}{144}}\)
27 Tính
A= \(\dfrac{10\dfrac{1}{3}.(26\dfrac{1}{3}-\dfrac{176}{7})-\dfrac{12}{11}.(\dfrac{10}{3}-1,75}{(\dfrac{5}{91-0,25)}.\dfrac{60}{11}-1}\)
Tìm x \(\in\) Z biết :
a ) \(\dfrac{1}{2}-\) (\(\dfrac{1}{2}-\dfrac{3}{2}\) ) \(\le x\le\dfrac{37}{24}-\left(\dfrac{1}{8}-\dfrac{2}{3}\right)\)
b ) \(\dfrac{-1}{23}+\dfrac{9}{-69}-\dfrac{7}{23}< \dfrac{x}{23}\le\dfrac{2}{46}-\dfrac{8}{23}\)
giúp mình với
Cho \(\dfrac{1}{x}=\dfrac{3}{y}=\dfrac{4}{z}\). Cmr (x+3y+4z)2=26(x2+9y2+16z2)
\(\dfrac{x+4}{2000}+\dfrac{x+3}{2001}=\dfrac{x+2}{2002}+\dfrac{x+1}{2003}\)
1/* Chứng minh rằng:
\(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+\dfrac{1}{5\times6}+...\dfrac{1}{49\times50}=\dfrac{1}{26}+\dfrac{1}{27}+\dfrac{1}{28}+..+\dfrac{1}{50}\)
2/* Cho:
A=\(\dfrac{1}{1\times2}+\dfrac{1}{3\times4}+\dfrac{1}{5\times6}+.....+\dfrac{1}{99\times100}\). Chứng minh rằng:\(\dfrac{7}{12}< A>\dfrac{5}{6}\)
Các bn giúp mk những bài này nha!
Cho:
A=\(\dfrac{1,11+0,19-1,3.2}{2,06+0,54}-\left(\dfrac{1}{2}+\dfrac{1}{3}\right):2\)
B=\(\left(5\dfrac{7}{8}-2\dfrac{1}{4}-0,5\right):2\dfrac{23}{26}\)
a)Rút gọn A và B
b)tìm x\(\in\)Z để A<x<B
Thực hiện phép tính (tính nhanh nếu có thể):
4) \(4\cdot\left(\dfrac{-1}{2}\right)^3+\left|-1\dfrac{1}{2}+\sqrt{\dfrac{9}{4}}\right|:\sqrt{25}\)
5) \(\left[6-3\cdot\left(\dfrac{-1}{3}\right)^2+\sqrt{\dfrac{1}{4}}\right]:\sqrt{0,\left(9\right)}\)
