Question

f(x)=x平方+【(x平方+1）分之1】,其中x属于[-1,1]的最小值为______

Answer 1

f(x)=x^2+1/(x^2+1)=x^2+1+1/(x^2+1)-1>=2-1=1

当且仅当x^1+1=1/(x^2+1)时等号成立,即x=0,所以f(x)在[-1,1]中最小值为1