How it is possible to find the value of `Delta U` and not the value of U?

How it is possible to find the value of Deltacup and not the value of cup ?

If U_x =x^2 ,find the value of Deltax^2 .

The process in which the value of Delta U=0 is :

If U_x = e^x ,find the value of Deltae^x

Delta U=0 for

If u_x = e^(ax) ,find the value of Deltae^(ax)

100 ml of a liquid is present in an insulated container at a pressure of 1 bar. The pressure is steeply increased to 100 bar. The volume of the liquid is decreased by 1 ml at this constant pressure. Find the values of Delta H and Delta U .

Find the value of int_(u)^(v)Mvdv