Saved Bookmarks
| 1. |
If `f : [2,oo) to R` be the function defined by `f(x)=x^(2)-4x+5,` then the range of f isA. RB. `[1,oo)`C. `[4,oo)`D. `[5,oo)` |
|
Answer» Correct Answer - B Given that, `f(x)= x^(2) -4x+5` Let ` y= x^(2) -4x+5` ` implies y= x^(2) -4x+4+1=(x-2)^(2)+1 ` ` implies (x-2)^(2)=y-1impliesx-2=sqrt(y-1)` `implies x=2+sqrt(y-1)` ` :. y-1 ge 0, y ge 1` Range `=[1, oo)` |
|