1 tìm x biết ;a, 0-|x + 1| = 5 b, 2 - | \(\frac{3}{4}\)- x | = \(\frac{7}{12}\)c, 2 | \(\frac{1}{2}\)x - \(\frac{1}{3}\)| - \(\frac{3}{2}\)= \(\frac{1}{4}\)d, | x - \(\frac{1}{3}\)| = \(\frac{5}{6}\)e, \(\frac{3}{4}\)- 2 | 2x - \(\frac{2}{3}\)| =...
Đọc tiếp
1 tìm x biết ;
a, 0-|x + 1| = 5
b, 2 - | \(\frac{3}{4}\)- x | = \(\frac{7}{12}\)
c, 2 | \(\frac{1}{2}\)x - \(\frac{1}{3}\)| - \(\frac{3}{2}\)= \(\frac{1}{4}\)
d, | x - \(\frac{1}{3}\)| = \(\frac{5}{6}\)
e, \(\frac{3}{4}\)- 2 | 2x - \(\frac{2}{3}\)| = 2
f, \(\frac{2x-1}{2}\)= \(\frac{5+3x}{3}\)
a: 0-|x+1|=5
=>|x+1|=0-5=-5<0(vô lý)
=>x∈∅
b: \(2-\left|\frac34-x\right|=\frac{7}{12}\)
=>\(\left|x-\frac34\right|=2-\frac{7}{12}=\frac{17}{12}\)
=>\(\left[\begin{array}{l}x-\frac34=\frac{17}{12}\\ x-\frac34=-\frac{17}{12}\end{array}\right.\Rightarrow\left[\begin{array}{l}x=\frac{17}{12}+\frac{9}{12}=\frac{26}{12}=\frac{13}{6}\\ x=-\frac{17}{12}+\frac34=-\frac{17}{12}+\frac{9}{12}=-\frac{8}{12}=-\frac23\end{array}\right.\)
c: \(2\left|\frac12x-\frac13\right|-\frac32=\frac14\)
=>\(\left|2\left(\frac12x-\frac13\right)\right|=\frac32+\frac14=\frac74\)
=>\(\left|x-\frac23\right|=\frac74\)
=>\(\left[\begin{array}{l}x-\frac23=\frac74\\ x-\frac23=-\frac74\end{array}\right.\Rightarrow\left[\begin{array}{l}x=\frac74+\frac23=\frac{21+8}{12}=\frac{29}{12}\\ x=-\frac74+\frac23=\frac{-21+8}{12}=-\frac{13}{12}\end{array}\right.\)
d: \(\left|x-\frac13\right|=\frac56\)
=>\(\left[\begin{array}{l}x-\frac13=\frac56\\ x-\frac13=-\frac56\end{array}\right.\Rightarrow\left[\begin{array}{l}x=\frac56+\frac13=\frac76\\ x=-\frac56+\frac13=-\frac36=-\frac12\end{array}\right.\)
e: \(\frac34-2\left|2x-\frac23\right|=2\)
=>\(2\left|2x-\frac23\right|=\frac34-2=-\frac54<0\) (vô lý)
=>x∈∅
f: \(\frac{2x-1}{2}=\frac{5+3x}{3}\)
=>3(2x-1)=2(3x+5)
=>6x-3=6x+10
=>-3=10(vô lý)
=>x∈∅