A positive charge Q is on the y-axis at a distance a from the origin, and another positive charge q is on the x-axis at a distance b from the origin. A) For what values(s) of b is the x-component of the force on q a minimum? B) For what values(s) of b is the x-component of the force on q a maximum? Ok so I know that when b is zero, there is no x component. To solve the maz I did the following Fx=kQq/(a+b)^2 soFx = (4πεQq/(a^2 +b^2))(b/dFx/db = ((4πεQq)/(a^2 +b^2)^1.5) -8πεQqb^2(1.5(a^2 +b^2)^0.5/(a^2 +b^2)^3 a^2 +b^2))= 4πεQqb/(a^2 +b^2)^1.5 I took the deriviative of Fx with respect to b, dFx/db = ((4πεQq)/(a^2 +b^2)^1.5) -8πεQqb^2(1.5(a^2 +b^2)^0.5/(a^2 +b^2)^3 (I don't know if this is right) to solve for b I got b=a/sqrt(8a^2q)^3 I'm pretty sure this is not right since on the website I use to submit my homework, there is only one space below the a for the maxima. Where I need to input my answers it says the following: a) Minima when b=___ and also as b approaches infinity b) Maxima when b= +-a/sqrt____ There's only space for one number on each blank. I assume a) is zero. but I dont know what to do with b.