f(x)=x2−3x+9 then the derivative of f(x) in the interval (0,5) is

$f (x) = \sqrt{x^{2} - 3 x + 9}$

$= \sqrt{{(x - 3)}^{2}}$

$f (x) = | x - 3 |$

$f (x) = {\begin{cases} x - 3, x \geq 3 \\ 3 - x, x < 3 \end{cases}$

$\Rightarrow f^{|} (x) = {\begin{matrix} 1, & i f x \geq 3 \\ - 1, & i f x < 3 \end{matrix}$

$f (x)$ is differentiable at all points on the interval $(0, 5)$ except at $x = 3$

$∴$ the derivative of $f (x)$ on the interval $(0, 5)$ does not exist.

$f (x) = \sqrt{x^{2} - 3 x + 9}$ then the derivative of $f (x)$ in the interval $(0, 5)$ is