Tìm x biết :
b) |x - 1| + 3x = 1
c) |2x - 1| = |2x + 3|
d) |x| + |x + 2| = 0
e) \(\left|x\left(x^2-\dfrac{5}{4}\right)\right|=x\)
Tìm x biết x thuộc Z
a) |x| < \(2\dfrac{4}{5}\)
b) |x| > \(11\dfrac{3}{8}\)
c) \(\left|x-\dfrac{5}{3}\right|< \dfrac{1}{3}\)
d) \(\left|x+\dfrac{11}{2}\right|>\left|-5,5\right|\)
e) \(\dfrac{7}{6}< \left|x-\dfrac{2}{3}\right|< \dfrac{26}{9}\)
f) \(\dfrac{2}{5}< \left|x-\dfrac{7}{5}\right|< \dfrac{3}{5}\)
Bất kì câu trả lời nào liên quan đến câu hỏi tớ đều tick nhé, nhưng nếu có bạn làm rồi mà một bạn khác làm lại thì tớ không tick
Câu 1:
b: \(\Leftrightarrow\left|x-1\right|=-3x+1\)
\(\Leftrightarrow\left\{{}\begin{matrix}x< =\dfrac{1}{3}\\\left(-3x+1-x+1\right)\left(-3x+1+x-1\right)=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x< =\dfrac{1}{3}\\\left(-4x+2\right)\cdot\left(-2x\right)=0\end{matrix}\right.\Leftrightarrow x=0\)
c: \(\Leftrightarrow\left[{}\begin{matrix}2x-1=2x+3\\2x+3=1-2x\end{matrix}\right.\Leftrightarrow4x=2\Leftrightarrow x=\dfrac{1}{2}\)
d: \(\Leftrightarrow\left\{{}\begin{matrix}x=0\\x+2=0\end{matrix}\right.\Leftrightarrow x\in\varnothing\)
e: \(\Leftrightarrow\left\{{}\begin{matrix}x>=0\\\left[x\left(x^2-\dfrac{5}{4}\right)-x\right]\left[x\left(x^2-\dfrac{5}{4}\right)+x\right]=0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x>=0\\x\left(x^2-\dfrac{9}{4}\right)\cdot x\cdot\left(x^2-\dfrac{1}{4}\right)=0\end{matrix}\right.\Leftrightarrow x\in\left\{0;\dfrac{1}{2};\dfrac{3}{2}\right\}\)