Solución

El rotacional es

rot  F=×F=ijkxyzPQR=(RyQz)i+(PzRx)j+(QxPy)k=(xzx)i+(x2yz)j+zk\begin{aligned} rot\;\bold{F} &= \nabla\times\bold{F}\\ &= \begin{vmatrix} \bold{i} & \bold{j} & \bold{k}\\ \frac{\partial}{\partial x} & \frac{\partial}{\partial y} & \frac{\partial}{\partial z}\\ P & Q & R\\ \end{vmatrix}\\ &= \big(R_y - Q_z\big)\bold{i} + \big(P_z - R_x\big)\bold{j} + \big(Q_x - P_y\big)\bold{k}\\ &= (xz - x)\bold{i} + \big(x^2 - yz\big)\bold{j} + z\bold{k}\\ \end{aligned}