x-128=\(\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
Tìm x biết :
x-128=\(\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
x - 128 = \(\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
⇔ x - 128 = \(\left(\dfrac{104}{21}-5\right):\left(\dfrac{-1}{42}\right):\left(\dfrac{-1}{64}\right)\)
⇔ x - 128 = \(\left(\dfrac{-1}{21}\right):\left(\dfrac{-1}{42}\right):\left(\dfrac{-1}{64}\right)\)
⇔ x - 128 = -128
⇔ x = -128 + 128
⇔ x = 0
Vậy x = 0
\(x-128=\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
\(\Rightarrow x-128=\left(-\dfrac{1}{21}\right):\left(-\dfrac{1}{42}\right):\left(-\dfrac{1}{64}\right)\)
\(\Rightarrow x-128=2:\left(-\dfrac{1}{64}\right)\)
\(\Rightarrow x-128=-128\)
\(\Rightarrow x=\left(-128\right)+128\)
\(\Rightarrow x=0\)
tìmx e Q
x-180=\(\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
\(x-180=\left(4\dfrac{20}{21}-5\right):\left(\dfrac{4141}{4242}-1\right):\left(\dfrac{636363}{646464}-1\right)\)
\(\Rightarrow x-180=\left(\dfrac{104}{21}-5\right):-\dfrac{1}{42}:-\dfrac{1}{64}\)
\(\Rightarrow x-180=-\dfrac{1}{21}:-\dfrac{1}{42}:-\dfrac{1}{64}\)
\(\Rightarrow x-180=-\dfrac{1}{21}\cdot-42:-\dfrac{1}{64}\)
\(\Rightarrow x-180=2\cdot-64\)
\(\Rightarrow x-180=-128\)
\(\Rightarrow x=-128+180\)
\(\Rightarrow x=52\)
\(x-128=\left(4\frac{20}{11}-5\right):\left(\frac{4141}{4242}-1\right):\left(\frac{636363}{646464}-1\right)\)
tim x biet :
x-128 = \(\left(4\frac{20}{21}-5\right):\left(\frac{4141}{4242}-1\right):\left(\frac{636363}{646464}-1\right)\)
x-128=-128(cái này tự ấn máy tính nha viết hết ra lâu lắm)
x=-128+128
x=0
ko biết đúng ko nữa nếu đúng thì tick cho mình nha
x-128=( 4+20/21 -5) : ( 4141/4242 -1) : (636363/646464-1)
4+20/21 là hỗn số nha
Bài 1;Tính
\(\frac{-7}{4}.\left(\frac{33}{12}+\frac{3333}{2020}+\frac{333333}{303030}+\frac{33333333}{42424242}\right)\)
Bài 2;Tìm x,biết:
\(x-128=\left(4\frac{20}{21}-5\right):\left(\frac{4141}{4242}-1\right):\left(\frac{636363}{646464}-1\right)\)
Bài 3;Với giá trị nào của x thì :
a,\(A=\left(x-\frac{3}{4}\right).\left(x+\frac{1}{2}\right)\)là số dương b,\(B=\frac{x-0,5}{x+1}\)là số âm
Bài 4:Tìm cặp số (x,y) thuộc Z để:
\(B=\frac{1}{x-y}:\frac{x+2}{2.\left(x-y\right)}\)là số nguyên
Chọn câu trả lời đúng \(\left(2x+\dfrac{1}{5}\right)\left(-\dfrac{3}{5}x+\dfrac{4}{7}\right)=0\) thì:
A. x = \(\dfrac{-1}{10}\) hoặc x = \(\dfrac{20}{21}\)
B. x = \(\dfrac{20}{21}\)
C. x = \(-\dfrac{1}{10}\)
D. x = \(-\dfrac{20}{21}\)
BT2: Tìm x
1) \(x.\left(\dfrac{124124}{125125}-1\right)=\dfrac{2222}{5555}:\left[\left(\dfrac{2010}{2121}-1\right):\left(\dfrac{4040}{4141}-1\right)\right]\)
\(x\left(\dfrac{124124}{125125}-1\right)=\dfrac{2222}{5555}:\left[\left(\dfrac{2010}{2121}-1\right):\left(\dfrac{4040}{4141}-1\right)\right]\)
\(x\left(\dfrac{124}{125}-1\right)=\dfrac{2}{5}:\left(-\dfrac{37}{707}:\dfrac{-1}{41}\right)\)
\(-\dfrac{1}{125}x=\dfrac{2}{5}:\dfrac{1517}{707}\)
\(-\dfrac{1}{125}x=\dfrac{1414}{7585}\)
\(x=\dfrac{1414}{7585}:\dfrac{-1}{125}\\ x=\dfrac{-35350}{1517}\)
\(A=\dfrac{1}{10}+\dfrac{1}{11}+\dfrac{1}{12}+...+\dfrac{1}{99}+\dfrac{1}{100}>1\)
\(\dfrac{2n+5}{n+2}\)
\(S=\dfrac{1}{20}+\dfrac{1}{21}+\dfrac{1}{22}+L+\dfrac{1}{29}\)
\(A=\dfrac{7}{4}.\left(\dfrac{3333}{1212}+\dfrac{3333}{2020}+\dfrac{3333}{3030}+\dfrac{3333}{4242}\right)\)
\(A=\dfrac{1}{4.5}+\dfrac{1}{5.6}+...+\dfrac{1}{48.49}+\dfrac{1}{49.50}\)
\(A=\dfrac{17}{1.3}+\dfrac{17}{3.5}+\dfrac{17}{5.7}+...+\dfrac{17}{49.51}\)
\(\dfrac{2n+5}{3n+1}\)
\(\left(\left|x\right|+\dfrac{2}{5}\right):\dfrac{2}{5}=1\)
\(\dfrac{1}{2}+\dfrac{1}{4}+\dfrac{1}{8}+\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{64}+\dfrac{1}{128}< 1\)
\(A=\dfrac{4}{1.3}+\dfrac{4}{3.5}+\dfrac{4}{5.7}+...+\dfrac{4}{99.101}\)
\(5.\left(\dfrac{1}{4}-\dfrac{1}{5}-\dfrac{1}{10}\right)\le\dfrac{x}{20}\le-3\left(\dfrac{1}{2}-\dfrac{1}{4}-\dfrac{1}{5}\right)\left(x\in Z\right)\)
\(\dfrac{2}{1.3}+\dfrac{2}{3.5}+\dfrac{2}{5.7}+...+\dfrac{2}{99.101}< 1\)
trả hiểu yêu cầu đề bài là j cả