Im having trouble with E4b2 I need to be finding the potenti

I\'m having trouble with E4b.2. I need to be finding the potential of this particle.

Solution

the electric field on the y-axis is,

    V = VL + VR

        = k(-2q)/(a^2+y^2)^1/2 + k(q)/(a^2+y^2)^1/2

        = kq / (a^2+y^2)^1/2

here, y takes the values from, - y to +y, y is the variable.