Question

tìm x ​|2.x+3|-2=3

Answer 1

\(\left|2x+3\right|-3=3\)

<=> \(\left|2x+3\right|=6\)

Ta có : \(\left|2x+3\right|=\left\{{}\begin{matrix}2x+3khix\ge\frac{-3}{2}\\-\left(2x+3\right)khix\le\frac{-3}{2}\end{matrix}\right.\)

Ta giải 2 phương trình

1) \(\left|2x+3\right|=6\) khi x ≥ \(\frac{-3}{2}\)

<=> 2x+3=6

<=> x= \(\frac{3}{2}\)

2) \(\left|2x+3\right|=6\) khi x ≤ \(\frac{-3}{2}\)

<=> -(2x+3)=6

<=> -2x-3=6

<=>x= \(\frac{-9}{2}\)

Answer 2

S những bài lớp lớn mà bn cứ đăng ở lớp 6 thế!!!

Answer 3

\(\left|2x+3\right|-2=3\)

\(\Leftrightarrow\left|2x+3\right|=5\)

\(\Leftrightarrow\left[{}\begin{matrix}2x+3=5khi2x+3\ge0\\-\left(2x+3\right)=5khi2x+3< 0\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}2x=2khix\ge-\frac{3}{2}\\-2x-3=5khix< -\frac{3}{2}\end{matrix}\right.\)

\(\Leftrightarrow\left[{}\begin{matrix}x=1khix\ge-\frac{3}{2}\left(tm\right)\\x=-4khix< -\frac{3}{2}\left(tm\right)\end{matrix}\right.\)

Vậy x\(\in\left\{1;-4\right\}\)

Answer 4

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

vậy x={1;-4}

Answer 5

/2.x+3/-2=3

/2.x+3/=3+2

/2.x+3/=5

=>2.x+3=5 hoặc 2.x+3=(-5)

*2.x+3=5

2.x=5-3

2.x=2

x=2:2

x=1

*2.x+3=(-5)

2.x=(-5)-3

2.x=(-8)

x=(-8):2

x=(-4)

Vậy x= (-4) hoặc x=1