f (x) = xx has a stationary point at
Given equation is f (x) = xx
Let y= xx………(i)
Taking logarithm on both sides we get
log y=log (xx)
⇒ log y=x log x
Now applying first derivative, we get
Now applying the product rule of differentiation we get
Now applying the deravative we get
Substituting the value of y from equation (i), we get
Now we will find the critical point by equating equation (i) to 0, we get
xx (1+log x)=0
⇒ 1+log x =0 as xx cannot be equal to 0
⇒ log x=-1
But -1=log e-1
⇒ log x=log e-1
Equating the terms we get
x= e-1
Hence f(x) has a stationary point at
So the correct option is option B.