-
Nguyễn Huy Tú 17/03/2017 at 12:55
Put \(A=\left|m-2\right|+\left|m+3\right|\)
We have: \(A=\left|m-2\right|+\left|m+3\right|=\left|2-m\right|+\left|m+3\right|\)
Apply the inequality \(\left|a\right|+\left|b\right|\ge\left|a\right|+\left|b\right|\), we have:
\(A\ge\left|2-m+m+3\right|=\left|5\right|=5\)
The "=" sign occurs when \(\left\{{}\begin{matrix}2-m\ge0\\m+3\ge0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}m\le2\\m\ge-3\end{matrix}\right.\Rightarrow-3\le m\le2\)
So \(MIN_A=5\) when \(-3\le m\le2\)
Selected by MathYouLike -
¤« 08/04/2018 at 15:13
Put A=|m−2|+|m+3|
We have: A=|m−2|+|m+3|=|2−m|+|m+3|
Apply the inequality |a|+|b|≥|a|+|b|
, we have:
A≥|2−m+m+3|=|5|=5
The "=" sign occurs when {2−m≥0m+3≥0⇒{m≤2m≥−3⇒−3≤m≤2
So MINA=5
when −3≤m≤2
Find minimize |m−2|+|m+3|
?
By inequality |a|+|b|≥|a+b|
we have:
|m−2|+|m+3|=|2−m|+|m+3|
≥|2−m+m+3|=5
Done !
-
Ace Legona 17/03/2017 at 11:52
Find minimize \(|m-2|+|m+3|\) ?
By inequality \(\left|a\right|+\left|b\right|\ge\left|a+b\right|\) we have:
\(\left|m-2\right|+\left|m+3\right|=\left|2-m\right|+\left|m+3\right|\)
\(\ge\left|2-m+m+3\right|=5\)
Done !