Tham khảo nha nhóc
https://olm.vn/hoi-dap/detail/223396249611.html
Tương tự à
Áp dụng BĐT \(\left|x\right|+\left|y\right|\ge\left|x+y\right|\)
\(\Rightarrow A=\left|x+2018\right|+\left|2019-x\right|\ge\left|\left(x+2018\right)+\left(2019-x\right)\right|=4037\)
\(\Rightarrow A_{min}=4037\)(Dấu "="\(\Leftrightarrow x\le2019\))
Kiệt sai rồi em
Đáp án Min A=4037 \(\Leftrightarrow-2018\le x\le2019\)
Ta có: \(B=\left|2x+2018\right|+\left|2x-2019\right|=\left|2x+2018\right|+\left|2019-2x\right|\)
Áp dụng BĐT \(\left|x\right|+\left|y\right|\ge\left|x+y\right|\)
\(B=\left|2x+2018\right|+\left|2019-2x\right|\ge\left|2x+2018+2019-2x\right|=4037\)
\(\Rightarrow B_{min}=4037\)
\(A_{min}=4037\)(Dấu"="\(\Leftrightarrow-2018\le x\le2019\))
\(A=|x+2018|+|2019-x|\)\(\ge\)\(|x+2018+2019-x|\)\(=|4037|=4037\)
\(\Leftrightarrow\left(x+2018\right)\left(x+2019\right)\ge0\)
\(.........\)
\(B=|2x+2018|+|2x-2019|\)\(=|2x+2018|+|2019-2x|\)
\(\ge|2x+2018+2019-2x|\)\(=|4037|=4037\)
\(\Leftrightarrow\left(2x+2018\right)\left(2019-2x\right)\ge0\)
\(.......\)
Thank all nha
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