Question

当x取何值时,分式(6x的平方+10)除以(x的平方+2)有最小值,最小值是多少

Answer 1

(6x^2+10)/(x^2+2) =(6x^2+12-2)/(x^2+2) =[6(x^2+2)-2]/(x^2+2) =6-2/(x^2+2) 当x=0时,2/(x^2+2)最大=1 此时(6x^2+10)/(x^2+2)最小=5