Question

Particle 1 and 2 of charge q1 = q2 = +3.3*10-19 C are on the y-axis at distance d = 17cm from the origin. Particle 3 of charge q3 = 6.4*10-19 C is moved gradually along the x-axis from x = 0 to x = 5.0cm. At what values of x will the magnitude of the electrostatic force on the third particle from the other two particle be
1) Minimum
2) Maximum