The distance between the orthocentre and circumcentre  of triangle with vertices (1,2),(2,1) and 3+32,3+32 is

Let A(1,2),B(2,1),C3+32,3+32 be the vertices of the triangle. AB=2−12+1−22=2BC=3+32−22+3+32−12=3−122+3+122       =84=2CA=2ΔABC is equilateral. ∴ orthocentre and circumcentre coincide with centroid.  The distance between orthocentre and circumcentre is zero.