a, ta có: (2x-3).(6-2x)=0
=>(2x-3)=0 hoặc (6-2x)=0
+, nếu 2x-3=0 thì x= 2/3 (1)
+, nếu 6-2x=0 thì x= 3 (2)
vì x thuộc Z nên từ (1) và(2) => x=3
vậy x=3
a)TH1: 2x-3=0
2x=3
x=3/2
TH2; 6-2x=0
2x=6
x=3
a) ( 2x - 3 )( 6 - 2x ) = 0
<=> \(\orbr{\begin{cases}2x-3=0\\6-2x=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=\frac{3}{2}\\x=3\end{cases}}\)
b) | 1/2x - 1/3 | - 3/2 = 1/4
<=> | 1/2x - 1/3 | = 7/4
<=> \(\orbr{\begin{cases}\frac{1}{2}x-\frac{1}{3}=\frac{7}{4}\\\frac{1}{2}x-\frac{1}{3}=-\frac{7}{4}\end{cases}}\)
<=> \(\orbr{\begin{cases}x=\frac{25}{6}\\x=-\frac{17}{6}\end{cases}}\)
c) ( 2x + 3/5 )2 = 9/25
<=> ( 2x + 3/5 )2 = ( ±3/5 )2
<=> \(\orbr{\begin{cases}2x+\frac{3}{5}=\frac{3}{5}\\2x+\frac{3}{5}=-\frac{3}{5}\end{cases}}\)
<=> \(\orbr{\begin{cases}x=0\\x=-\frac{3}{5}\end{cases}}\)
d) 11/3( 1/5 - 1/2 ) ≤ x ≤ 3/11( 1/5 + 2/3 - 1/2 )
<=> -11/10 ≤ x ≤ 1/10
e) 4, 25 - ( 25/8 - 1, 105 ) < x < 9,1 - ( 6, 85 - 11/4 )
<=> 223/100 < x < 5
<=> 223/100 < x < 500/100
ý d) với e) nó nhiều số lắm nên k liệt kê hết được đâu :))
b) \(|\)1/2x-1/3\(|\) - 3/2 = 1/4
\(|\)1/2x-1/3\(|\)= 1/4+3/2=7/4
Th1: 1/2x-1/3=7/4
1/2x=7/4+1/3
1/2x=25/12
x=25/12:1/2
x=25/6
Th2: 1/2x-1/3=-7/4
1/2x= -7/4+1/3
1/2x=-17/12
x= -17/12:1/2
x=-17/6
\(a,\left(2x-3\right).\left(6-2x\right)=0\)
\(\Rightarrow\orbr{\begin{cases}2x-3=0\\6-2x=0\end{cases}}\Rightarrow\orbr{\begin{cases}2x=3\\2x=6\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{3}{2}\\x=3\end{cases}}\)
\(b,|\frac{1}{2}.x-\frac{1}{3}|-\frac{3}{2}=\frac{1}{4}\)
\(|\frac{1}{2}.x-\frac{1}{3}|=\frac{1}{4}+\frac{3}{2}\)
\(|\frac{1}{2}.x-\frac{1}{3}|=\frac{7}{4}\)
\(\Rightarrow\orbr{\begin{cases}\frac{1}{2}x-\frac{1}{3}=\frac{7}{4}\\\frac{1}{2}x-\frac{1}{3}=-\frac{7}{4}\end{cases}}\Rightarrow\orbr{\begin{cases}\frac{1}{2}x=\frac{25}{12}\\\frac{1}{2}x=\frac{-17}{12}\end{cases}}\Rightarrow\orbr{\begin{cases}x=\frac{25}{6}\\x=\frac{-17}{6}\end{cases}}\)
\(c,\left(2x+\frac{3}{5}\right)^2=\frac{9}{25}\)
\(\left(2x+\frac{3}{5}\right)^2=\left(\frac{3}{5}\right)^2\)
\(\Rightarrow\orbr{\begin{cases}2x+\frac{3}{5}=\frac{3}{5}\\2x+\frac{3}{5}=\frac{-3}{5}\end{cases}}\Rightarrow\orbr{\begin{cases}2x=0\\2x=\frac{-6}{5}\end{cases}}\Rightarrow\orbr{\begin{cases}x=0\\x=\frac{-3}{5}\end{cases}}\)
\(d,\frac{11}{3}.\left(\frac{1}{5}-\frac{1}{2}\right)\le x\le\frac{3}{11}.\left(\frac{1}{5}+\frac{2}{3}-\frac{1}{2}\right)\)
\(\Rightarrow\frac{11}{3}.\frac{-3}{10}\le x\le\frac{3}{11}.\frac{11}{30}\)
\(\Rightarrow\frac{-11}{10}\le x\le\frac{3}{10}\)
\(\Leftrightarrow x=\left\{\frac{-11}{10};\frac{-10}{10};\frac{-9}{10};...;\frac{2}{10};\frac{3}{10}\right\}\)
\(e,4,25-\left(\frac{25}{8}-1,105\right)< x< 9,1-\left(6,85-\frac{11}{4}\right)\)
\(\Rightarrow4,25-2,02< x< 9,1-4,1\)
\(\Rightarrow2,23< x< 5\)
\(\Leftrightarrow x=\left\{2,24;2,25;2,26;.....;4,99;5\right\}\)
Học tốt
úi e nhầm đè
cái kia phải là 4,85 cứ ko phải 4,25 sorry mn mong mn giúp e
