x.(x+7)=0 (x+12).(x-3)=0 (-x+5).(3-x)=0 x(2+x)>(7-x)=0 (x-1).(x+2).(-x-3)=0 nhớ giúp mik, mik cho 5 sao 23/10/2021 Bởi Julia x.(x+7)=0 (x+12).(x-3)=0 (-x+5).(3-x)=0 x(2+x)>(7-x)=0 (x-1).(x+2).(-x-3)=0 nhớ giúp mik, mik cho 5 sao
Giải thích các bước giải : `+)x(x+7)=0` `<=>`\(\left[ \begin{array}{l}x=0\\x+7=0\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=0\\x=-7\end{array} \right.\) Vậy : `x∈{-7; 0}` `+)(x+12)(x-3)=0` `<=>`\(\left[ \begin{array}{l}x+12=0\\x-3=0\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=-12\\x=3\end{array} \right.\) Vậy : `x∈{-12; 3}` `+)(-x+5)(3-x)=0` `<=>`\(\left[ \begin{array}{l}-x+5=0\\3-x=0\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=5\\x=3\end{array} \right.\) Vậy : `x∈{3; 5}` `+)x(x+2)(7-x)=0` `<=>`\(\left[ \begin{array}{l}x=0\\x+2=0\\7-x=0\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=0\\x=-2\\x=7\end{array} \right.\) Vậy : `x∈{-2; 0; 7}` `+)(x-1)(x+2)(-x-3)=0` `<=>`\(\left[ \begin{array}{l}x-1=0\\x+2=0\\-x-3=0\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=1\\x=-2\\x=-3\end{array} \right.\) Vậy : `x∈{-3; -2; 1}` Bình luận
Đáp án + Giải thích các bước giải: `x.(x+7)=0 ` \(\left[ \begin{array}{l}x=0\\x+7=0\end{array} \right.\) \(\left[ \begin{array}{l}x=0\\x=-7\end{array} \right.\) $$$$ `(x+12).(x-3)=0` \(\left[ \begin{array}{l}x+12=0\\x-3=0\end{array} \right.\) \(\left[ \begin{array}{l}x=-12\\x=3\end{array} \right.\) $$$$ `(-x+5).(3-x)=0` `( x – 5 ) . ( 3 – x ) = 0 ` \(\left[ \begin{array}{l}x-5=0\\3 -x=0\end{array} \right.\) \(\left[ \begin{array}{l}x=5\\x=3\end{array} \right.\) $$$$ `x(2+x)(7-x)=0` \(\left[ \begin{array}{l}x= 0\\2+x=0\\7-x=0\end{array} \right.\) \(\left[ \begin{array}{l}x=0\\x=-2\\x=7\end{array} \right.\) $$$$ `(x-1).(x+2).(-x-3)=0` \(\left[ \begin{array}{l}x – 1 = 0\\x+2=0\\ -x -3 =0\end{array} \right.\) \(\left[ \begin{array}{l}x =1\\x=-2\\x=-3\end{array} \right.\) Bình luận
Giải thích các bước giải :
`+)x(x+7)=0`
`<=>`\(\left[ \begin{array}{l}x=0\\x+7=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=0\\x=-7\end{array} \right.\)
Vậy : `x∈{-7; 0}`
`+)(x+12)(x-3)=0`
`<=>`\(\left[ \begin{array}{l}x+12=0\\x-3=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=-12\\x=3\end{array} \right.\)
Vậy : `x∈{-12; 3}`
`+)(-x+5)(3-x)=0`
`<=>`\(\left[ \begin{array}{l}-x+5=0\\3-x=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=5\\x=3\end{array} \right.\)
Vậy : `x∈{3; 5}`
`+)x(x+2)(7-x)=0`
`<=>`\(\left[ \begin{array}{l}x=0\\x+2=0\\7-x=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=0\\x=-2\\x=7\end{array} \right.\)
Vậy : `x∈{-2; 0; 7}`
`+)(x-1)(x+2)(-x-3)=0`
`<=>`\(\left[ \begin{array}{l}x-1=0\\x+2=0\\-x-3=0\end{array} \right.\)
`<=>`\(\left[ \begin{array}{l}x=1\\x=-2\\x=-3\end{array} \right.\)
Vậy : `x∈{-3; -2; 1}`
Đáp án + Giải thích các bước giải:
`x.(x+7)=0 `
\(\left[ \begin{array}{l}x=0\\x+7=0\end{array} \right.\)
\(\left[ \begin{array}{l}x=0\\x=-7\end{array} \right.\)
$$$$
`(x+12).(x-3)=0`
\(\left[ \begin{array}{l}x+12=0\\x-3=0\end{array} \right.\)
\(\left[ \begin{array}{l}x=-12\\x=3\end{array} \right.\)
$$$$
`(-x+5).(3-x)=0`
`( x – 5 ) . ( 3 – x ) = 0 `
\(\left[ \begin{array}{l}x-5=0\\3 -x=0\end{array} \right.\)
\(\left[ \begin{array}{l}x=5\\x=3\end{array} \right.\)
$$$$
`x(2+x)(7-x)=0`
\(\left[ \begin{array}{l}x= 0\\2+x=0\\7-x=0\end{array} \right.\)
\(\left[ \begin{array}{l}x=0\\x=-2\\x=7\end{array} \right.\)
$$$$
`(x-1).(x+2).(-x-3)=0`
\(\left[ \begin{array}{l}x – 1 = 0\\x+2=0\\ -x -3 =0\end{array} \right.\)
\(\left[ \begin{array}{l}x =1\\x=-2\\x=-3\end{array} \right.\)