0,1(6)=...
tìm x: (x - 0,1)^6 = (x - 0,1)^4
(x - 0,1)⁶ = (x - 0,1)⁴
(x - 0,1)⁶ - (x - 0,1)⁴ = 0
(x - 0,1)⁴.[(x - 0,1)² - 1] = 0
(x - 0,1)⁴ = 0 hoặc (x - 0,1)² - 1 = 0
*) (x - 0,1)⁴ = 0
x - 0,1 = 0
x = 0,1
*) (x - 0,1)² - 1= 0
(x - 0,1)² = 1
x - 0,1 = 1 hoặc x - 0,1 = -1
**) x - 0,1 = 1
x = 1 + 0,1
x = 1,1
*) x - 0,1 = -1
x = -1 + 0,1
x = -0,9
Vậy x = -0,9; x = 0,1; x = 1,1
(1/6+0,1+1/15):(1,6+0,1-1/15)/(0,5-1/3+1/4-1/5):(1/4-1/6)
Tính
0,1(6) + 1, ( 3 )
1,(3) + 0,1(2) . \(2\frac{8}{11}\)
0,(6) + 1,(6)
3,(6) + 1,(36) x \(2\frac{1}{5}\)
a) 0,16 + 1,3
= \(\frac{4}{25}+\frac{13}{10}\)
= \(\frac{40}{250}+\frac{325}{250}\)
= \(\frac{73}{50}\)
b) 1,3 + 0,12 . \(2\frac{8}{11}\)
= \(\frac{13}{10}+\frac{3}{25}\times\frac{30}{11}\)
= \(\frac{13}{10}+\frac{18}{55}\)
= \(\frac{143}{110}+\frac{36}{110}\)
= \(\frac{179}{110}\)
c) 0,6 + 1,6
= \(\frac{3}{5}+\frac{8}{5}\)
= \(\frac{11}{5}\)
d) 3,6 + 1,36 \(\times\)\(2\frac{1}{5}\)
= \(\frac{18}{5}+\frac{34}{25}\times\frac{11}{5}\)
= \(\frac{18}{5}+\frac{374}{125}\)
= \(\frac{450}{125}+\frac{374}{125}\)
= \(\frac{824}{125}\)
Tính:
\(\begin{array}{l}a)2.\sqrt 6 .( - \sqrt 6 );\\b)\sqrt {1,44} - 2.{(\sqrt {0,6} )^2};\\c)0,1.{(\sqrt 7 )^2} + \sqrt {1,69} ;\\d)( - 0,1).{(\sqrt {120} )^2} - \frac{1}{4}.{(\sqrt {20} )^2}\end{array}\)
\(\begin{array}{l}a)2.\sqrt 6 .( - \sqrt 6 )\\ = - 2.\sqrt 6 .\sqrt 6 \\ = - 2.{(\sqrt 6 )^2}\\ = - 2.6\\ = - 12\\b)\sqrt {1,44} - 2.{(\sqrt {0,6} )^2}\\ = 1,2 - 2.0,6\\ = 1,2 - 1,2\\ = 0\\c)0,1.{(\sqrt 7 )^2} + \sqrt {1,69} \\ = 0,1.7 + 1,3 \\= 0,7 + 1,3 \\= 2\\d)( - 0,1).{(\sqrt {120} )^2} - \frac{1}{4}.{(\sqrt {20} )^2} \\= ( - 0,1).120 - \frac{1}{4}.20\\ = - 12 - 5\\ = - (12 + 5)\\ = - 17\end{array}\)
a: \(=-2\sqrt{6}\cdot\sqrt{6}=-2\cdot\sqrt{6\cdot6}=-2\cdot6=-12\)
b: \(=1.2-2\cdot0.6=1.2-1.2=0\)
c: \(=0.1\cdot7+1.3=0.7+1.3=2\)
d: \(=-0.1\cdot120-\dfrac{1}{4}\cdot20=-12-5=-17\)
0,5+0,(3)-0,1(6)/2,5+1(6)-0,8(3)
0,5+0,(3)-0,1(6)/2,5+1,(6)-0,8(3)
\(\dfrac{0.5+0.\left(3\right)-0.1\left(6\right)}{2.5+1.\left(6\right)-0.8\left(3\right)}\)
\(=\dfrac{\dfrac{1}{2}+\dfrac{1}{3}-\dfrac{1}{6}}{\dfrac{5}{2}+\dfrac{5}{3}-\dfrac{5}{6}}=\dfrac{1}{5}\)
0.5+0,(3)+0,1(6)trên2.5+1.(6)-0.8(3)
0,1(6) bang may?
tìm x biết
-2,(6)*x=0,1(6)
\(-2,\left(6\right).x=0,1\left(6\right)\\ \Leftrightarrow x=0,1\left(6\right):-2,\left(6\right)\\ \Leftrightarrow x=\left[0,1+\dfrac{6.1}{99}\right]:\left[-2-\dfrac{6.1}{9}\right]\\ \Leftrightarrow x=-\dfrac{53}{880}\)
\(-2,\left(6\right).x=0,1\left(6\right)\)
\(\Leftrightarrow\dfrac{-8}{3}x=\dfrac{1}{6}\)
\(\Rightarrow x=\dfrac{1}{6}:\dfrac{-8}{3}\)
\(\Rightarrow x=\dfrac{-1}{16}\)
( ko chắc chắn mấy )
-2,(6).x=0,1(6)
-\(\dfrac{8}{3}\).x=\(\dfrac{1}{6}\)
x=\(\dfrac{1}{6}\):(-\(\dfrac{8}{3}\))
x=\(\dfrac{-1}{16}\)