Question

Can someone help me find E_max? (Electromagnetism problem)

Answer 1

I've found x, but can't figure out how to get $$E_{max}$$

Answer 2

I found a solution online with an explanation

Answer 3

\[dE_x = k_e {dq\over r^2} cos\theta =k_e {dq\over {a^2+x^2}} cos\theta \]

Answer 4

do you still need help then?