Distance between two points in n-dimensional space

MATL, 2 bytes

ZP

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The ZP function (corresponding to MATLAB's pdist2) computes all pairwise distances between two sets of points, using Euclidean distance by default. Each set of points is a matrix, and each point is a row. In this case it produces a single result, which is the distance between the two points.

MATL, 4.0 3 bytes

Thanks for -1 by @AndrasDeak!

-Zn

Reads two vectors (via implicit input that is requested by -) then substracts those and calculates the norm of their difference with Zn.

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Pyth, 2 bytes

.a

.a - L2 norm of vector difference of A[0] and A[1].

Literally a function that does this problem

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