The minimum value of $f(x)=x^{2}+\frac{250}{x}$ is _______________
The given function is $f(x)=x^{2}+\frac{250}{x}, x \neq 0$.
$f(x)=x^{2}+\frac{250}{x}$
Differentiating both sides with respect to x, we get
$f^{\prime}(x)=2 x-\frac{250}{x^{2}}$
For maxima or minima,
$f^{\prime}(x)=0$
$\Rightarrow 2 x-\frac{250}{x^{2}}=0$
$\Rightarrow x^{3}=\frac{250}{2}=125$
$\Rightarrow x=5$
Now,
$f^{\prime \prime}(x)=2+\frac{500}{x^{3}}$
At x = 5, we have
$f^{\prime \prime}(5)=2+\frac{500}{(5)^{3}}=2+\frac{500}{125}=2+4=6>0$
So, x = 5 is the point of local minimum.
$\therefore$ Minimum value of $f(x)=f(5)=(5)^{2}+\frac{250}{5}=25+50=75$ $\left[f(x)=x^{2}+\frac{250}{x}\right]$
Thus, the minimum value of the given function is 75.
The minimum value of $f(x)=x^{2}+\frac{250}{x}$ is ___75____.