Let f (x) be a function defined by `f(x)= int_(1)^(x) t(t^(2)-3t +2) dt, 1 le xxle 3 ` Then, the range of f (x) is

Answer

2

Explanation

`f^(')(x)=x(x^(2)-3x+2)=x(x-1)(x-2)` the sign scheme for `f^(')(x)` is as below
`:.f^(')le0` in `1lexle2` and `f^(')(x)ge0` in `2lexle5`
`:.f(x)` is decreasing in `[1,2]` and increasing in `[2,3]`
maximum `f(x)=` the greatest among `{f(1),f(3)}`
`f(1)=int_(1)^(1)x(x^(2)-3x+2)dx=0,f(3)=int_(1)^(3)x(x^(2)-3x+2)dx=2`
`:.` maximum `f(x)=2`