Đáp án:
a) `S={1/2}`
c) `S={4;0}`
e) `S={5;-1/5}`
Giải thích các bước giải:
a) `|x-2|=x+1(x>=-1)`
`->`\(\left[ \begin{array}{l}x-2=x+1\\2-x=x+1\end{array} \right.\)
`->` \(\left[ \begin{array}{l}-2=1 (Vô lý)\\1=2x\end{array} \right.\)
`->x=1/2(TM)`
`->S={1/2}`
c) `2|x-1|=x+2(x>=-2)`
`->`\(\left[ \begin{array}{l}2(x-1)=x+2\\2(1-x)=x+2\end{array} \right.\)
`->`\(\left[ \begin{array}{l}2x-2=x+2\\2-2x=x+2\end{array} \right.\)
`->`\(\left[ \begin{array}{l}x=4\\3x=0\end{array} \right.\)
`->`\(\left[ \begin{array}{l}x=4(TM)\\x=0(TM)\end{array} \right.\)
`->S={4;0}`
e) `|3x-2|=2x+3 (x>=-3/2)`
`->` \(\left[ \begin{array}{l}3x-2=2x+3\\2-3x=2x+3\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=5\\5x=-1\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=5(TM)\\x=-\dfrac{1}{5}(TM)\end{array} \right.\)
`-> S={5;-1/5}`
