Consider a collection of three point charges. Two equal charges, Q1 = Q2 = 3.0 nC, are on the x-axis at the points x = 4.0 cm and x = -4.0 cm. The third charge is Q3= -3.0 nC, and is on the y-axis at the point y = 8.0 cm.
What is the the electricrostatic potential due to these three charges at a point on the y-axis at y = 4.0 cm?