"Differentiate" action is very useful when you need to take the derivative of the both sides of an equation.
For example, here we will demonstrate how to use this action to do implicit differentiation.
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REMARK: If the "Equations: Solve for" action is not available to you (disabled by your instructor), you will have to solve the equation for 
manually. In such a case, please refrain from writing something like
since here the system thinks you are evaluating at the expression 
. It is always safer to write on the right hand side of the expression i.e.
Or to make sure to add a product (* i.e. shift 8) betweenand the expression i.e.
Because otherwise the system will give you an error message as the following once you divide both sides of the equation by the expression :
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Hope you have found this helpful. In case you have questions or concerns on using "Equations: Differentiate" action do not hesitate to contact us here.