I know that the potential at any point P is the sum of the two potentials of a dipole. But we make two assumptions to get an equation:(adsbygoogle = window.adsbygoogle || []).push({});

1 - the distance from the dipole to P is very large relative to the dipole distance (d)

2 - we also make the assumption that r2 - r1 = dcosθ

r2 and r1 is the distance from the dipole charges to P - how do we get cosine?

I don't understand the second assumption. Any help will be nice

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# Homework Help: Potential of a dipole at P?

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