Applied maths help.Derive an expression for the gravitational potential Vgrav at a general position x on the ?

applied maths help.Derive an expression for the gravitational potential Vgrav at a general position x on the ?

Derive an expression for the gravitational potential Vgrav at a general position x on the x-axis.?
In a system where other gravitational influences can be discounted, two particles of equal mass m are fixed at positions x = 0 and x = x0 on the x-axis.

1)Derive an expression for the gravitational potential Vgrav at a general position x on the x-axis.
2)What is the physical significance of a point where dVgrav/dx = 0?

3)State the coordinates of such a point in this system. You should not
require any mathematics for this, but you must justify your choice.
4)A third particle, which is free to move, is placed at the point where
dVgrav/dx = 0. Based on the shape of the potential as it appears in your graph, comment on what would happen if this new particle was moved slightly away from this point along the x-axis.

can an one help me please ?