Maximum and minimum of an expression: fMax fMin

fMax and fMin take one or two arguments : an expression of a variable and the name of this variable (by default x).
fMax returns the abscissa of a maximum of the expression.
fMin returns the abscissa of a minimum of the expression.
Input :

fMax(sin(x),x)

Or :

fMax(sin(x))

Or :

fMax(sin(y),y)

Output :

pi/2

Input :

fMin(sin(x),x)

Or :

fMin(sin(x))

Or :

fMin(sin(y),y)

Output :

-pi/2

Input :

fMin(sin(x)^2,x)

Output :

0