\frac{d}{dt}[\hat{x_H},\hat{p_H}]=[\frac{d}{dt}\hat{x_H},\hat{p_H}]+[\hat
{x_H},\frac{d}{dt}\hat{p_H}]=\frac{i}{\hbar}([[\hat{H},\hat{x_H}],\hat{p_H}]+[\hat{x_H},[\hat{H},\hat{p_H}]])=
=-\frac{i}{\hbar}([\hat{p_H},[\hat{H},\hat{x_H}]]+[\hat{x_H},[\hat{p_H},\hat{H}]]+[\hat{H},[\hat{x_H},\hat{p_H}]])
+\frac{i}{\hbar}[\hat{H},[\hat{x_H},\hat{p_H}]]