Question

Giúp với

Answer 1

a) \(\Rightarrow\left|x\right|=\dfrac{16}{5}\Rightarrow\left[{}\begin{matrix}x=\dfrac{16}{5}\\x=-\dfrac{16}{5}\end{matrix}\right.\)

b) \(\Rightarrow\left[{}\begin{matrix}x+1=6\\x+1=-6\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=5\\x=-7\end{matrix}\right.\)

c) \(\Rightarrow S=\varnothing\left(do.\left|x\right|\ge0\forall x\right)\)

d) \(\Rightarrow\left|x+\dfrac{3}{4}\right|=\dfrac{1}{2}\Rightarrow\left[{}\begin{matrix}x+\dfrac{3}{4}=\dfrac{1}{2}\\x+\dfrac{3}{4}=-\dfrac{1}{2}\end{matrix}\right.\)\(\Rightarrow\left[{}\begin{matrix}x=-\dfrac{1}{4}\\x=-\dfrac{5}{4}\end{matrix}\right.\)

e) \(\Rightarrow\left|x+\dfrac{4}{15}\right|=\dfrac{8}{5}\Rightarrow\left[{}\begin{matrix}x+\dfrac{4}{15}=\dfrac{8}{5}\\x+\dfrac{4}{15}=-\dfrac{8}{5}\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{4}{3}\\x=-\dfrac{28}{15}\end{matrix}\right.\)

Answer 2

a) \(\left|x\right|=3\dfrac{1}{5}=\dfrac{16}{5}\Rightarrow x=\pm\dfrac{16}{5}\)

Vậy \(x=\pm\dfrac{16}{5}\)

b) \(\left|x+1\right|=6\Rightarrow x+1=\pm6\)

TH1: \(x+1=6\Rightarrow x=6-1=5\)

TH2: \(x+1=-6\Rightarrow x=-6-1=-7\)

Vậy \(x=\left\{5;-7\right\}\)

b) \(\left|x\right|=-2,1\)

Vì \(\left|x\right|\ge0\) nên x không có giá trị thỏa mãn