1. The problem statement, all variables and given/known data 2 positive charges are placed on the why axis. one is at y=+a the other at y=-a. show that the e field where x is much smaller than a is approximately equal to (2kqx)/a^3. The 1st part of the question was to show that the e field = (2kqx/(x^2+a^2)^1.5) I did that part already so we can just use that equation. 3. The attempt at a solution okay so, using the equation (2kqx/(x^2+a^2)^1.5) to do this part where x is much smaller than a means that x is approaching 0. so shouldn't the whole e field be approx = to 0 instead of like the equation they gave (2kqx)/a^3. where they only got rid of the x at the bottom and not the one at the top?