ta co :
|x-2|≥0 →-|x-2|≤0
10-|x-2|≤10-0=10
GTLN cua A = 10
\(A=10-\left|x-2\right|=-\left|x-2\right|+10\)
+Có: \(-\left|x-2\right|\le0với\forall x\\ \Rightarrow-\left|x-2\right|+10\le10\\ \Leftrightarrow A\le10\)
+Dấu ''='' xảy ra khi \(\left|x-2\right|=0\Leftrightarrow x=2\)
+Vậy \(A_{min}=10\) khi \(x=2\)
\(A=10-\left|x-2\right|\)
Ta có: \(\left|x-2\right|\ge0\) \(\forall x.\)
\(\Rightarrow-\left|x-2\right|\le0\) \(\forall x\)
\(\Rightarrow10-\left|x-2\right|\le10\)
\(\Rightarrow A\le10.\)
Dấu " = " xảy ra khi:
\(x-2=0\)
\(\Rightarrow x=0+2\)
\(\Rightarrow x=2\)
Vậy \(MAX_A=10\) khi \(x=2.\)
Chúc bạn học tốt!
