Derivative
- Thread starter mystxgon
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Dr.Peterson
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I'm guessing you meant dy/dx (2+x)^3(2-x)^3.
The easiest way to do this would involve combining in into [(2+x)(2-x)]^3 and simplifying further. The straightforward way would use the product rule and the chain rule. It can be a useful exercise to try a problem like this two or three ways.
I'll presume you checked the answer in some way and found it was correct. If so, then how can you be stupid if you got the answer eventually? We're all stupid temporarily from time to time!
HallsofIvy
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I was going to ask if you had ever taken a Calculus course but you pummeled yourself before I could do it!
For future reference when you want to differentiate something like (2+ x)^3(2- x)^3 the first thing you might think is "that's a product of (2+ x)^3 and (2- x)^3 so I need the product rule" and then taking tne derivatives of (2+ x)^3 and (2- x)^3.
At least that was my first thought- but then I quickly thought, "Wait, that's the same as ((2+ x)(2- x))^3= (4- x^2)^3" and that's simpler to differentiate. If that was your first thought, you are better than I am!
For future reference when you want to differentiate something like (2+ x)^3(2- x)^3 the first thing you might think is "that's a product of (2+ x)^3 and (2- x)^3 so I need the product rule" and then taking tne derivatives of (2+ x)^3 and (2- x)^3.
At least that was my first thought- but then I quickly thought, "Wait, that's the same as ((2+ x)(2- x))^3= (4- x^2)^3" and that's simpler to differentiate. If that was your first thought, you are better than I am!