ĐKXĐ: 4-(x-1)^2>=0
=>(x-1)^2<=4
=>-2<=x-1<=2
=>-1<=x<=3
\(\left(x-1\right)^2>=0\)
=>-(x-1)^2<=0
=>\(-\left(x-1\right)^2+4< =4\)
=>\(\sqrt{-\left(x-1\right)^2+4}< =2\)
Dấu = xảy ra khi x=1
\(\sqrt{4-\left(x-1\right)^2}>=0\forall x\) thỏa mãn ĐKXĐ
Dấu = xảy ra khi 4-(x-1)^2=0
=>(2-x+1)(2+x-1)=0
=>(3-x)(1+x)=0
=>x=3 hoặc x=-1