We can understand this through the figure
The charges are of the opposite nature
When the charges are of opposite nature but of equal magnitude.
From the figure it is clear that there is no any neutral point exists.
Two equal charges q of opposite sign are separated by a small distance '2l'. The electric potential at a point on the perpendicular bisector of the line joining the two charges at a distance r is :
Two equal charges ‘q′ of opposite sign are separated by a small distance ‘d′. The electric intensity ‘E′ at a point on the straight line passing through the two charges at a very large distance ‘r′ from the midpoint of two charges is :