"Work from the outside in" is a suggestion for how to organize our work when the derivatives become more difficult to manage. We want to start with the outer-most operation, and work in from there. The "outer-most" operation is the one that would be performed last if we were typing things into a calculator. This is similar to top-down design in computer programming.
Practice:
Find the derivative of 
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This function contains both a product and a quotient. Since the quotient is "outside" the product (that is, we would find the quotient after finding the product x2sin x), we start with the quotient rule. 
Now we need to use the product rule, in order to find one of the derivatives we need to finish applying the quotient rule! (x2sin x)' = 2xsin x + x2cos x. Then we can go back and finish with the quotient rule: 
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Find the derivative of 
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This function contains both a product and a quotient, and in this case the product is "outside" the quotient. We start with the product rule: 
In order to complete the use of the product rule, we need to find the derivative of the quotient: 
Now we can put this back into the product rule and finish the problem. 
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