The net force on the charge placed at origin

[Jai Singh]

Ques:
If infinite number of charges placed along x-axis .At x=1, 1μC , x=2, 2μC, x=3, 3μC so on. Find the net force on charge 1μC placed at origin.Formula used
(1/4πε)*q1*q2/r²

Solved from this formula but stuck in a series

 

[cnh1995]

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