I am doing applications of differentiation homework problems and have come to a function with constants involved; but the constants are defined as being any real #.

The function in question is F(x)=

where Z is a constant that is >= 0 and U is a constant that is any real number.

I differentiated it and was able to get it down to -(x-U)/(Z^3*sqrt(2*pi))*e^(-(x-u)^2/(2Z^2))

However the problem asks to find relative maxes and mins; which requires it to be set to zero. I solved this to be x=U...does this mean there are no relative maxes or mins?

Any help is appreciated! Thank you.