"Compute" action is recommended to be used when dealing with sub-problems.  For instance, if you are computing the derivative of a product, quotient or compositions of functions (chain rule), you might find "Compute" action very helpful. Please see the screen shot below to see a worked out example. Here "Compute" action is applied to  

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in the product.




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After result is added:



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Similarly, "compute" action can be applied to

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to complete the derivative of the product.