Inddd !
i need to find all values at which h has a local maximum and i need to find all local maximum values of h

All values at which h has a local maximum:

All local maximum values:

Step-by-step explanation:

The maximum of a function is described as the point in the graph where the value (in our case ) has the biggest magnitude, however we are asked for the local maximums which are the points where the value of has the biggest magintude amongst it´s surroundings values for .

As we can see in the graph we have two local maximums in the coordinates():

The two in this coordinates are thhe maximum values:

and the two in this coordinates will be the values at which h has a local maximum: