In the complex plane, set a point A.B.C, and the corresponding complex numbers are I, 1, 4 + 2I respectively. Through a, B, C, make the parallelogram ABCD, and find the length of the diagonal BD of the parallelogram

In the complex plane, set a point A.B.C, and the corresponding complex numbers are I, 1, 4 + 2I respectively. Through a, B, C, make the parallelogram ABCD, and find the length of the diagonal BD of the parallelogram

√13