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**shilz222** We all know that $\displaystyle \text{curl} \ \bold{F} = \left(\frac{\partial R}{\partial y} - \frac{\partial Q}{\partial z} \right) \bold{i} + \left(\frac{\partial P}{\partial z} - \frac{\partial R}{\partial x} \right) \bold{j} + \left(\frac{\partial Q}{\partial x} - \frac{\partial P}{\partial y} \right) \bold{k} $.

Here is a good technique to remember this:

Write down $\displaystyle P, Q, R $.

Put your left index finger on $\displaystyle R $. Now put your left middle finger on $\displaystyle Q $. Then go the opposite direction (like playing the piano). This is the first term. Do the same for the other terms. Keep playing this (as if you were playing the piano).

This is how I remember $\displaystyle \text{curl} \ \bold{F} $.