3x/(x+8). I need to use the 2nd derivative test to find the point(s) of inflection. I get confused about how to do derivatives of examples like this.
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Originally Posted by akuczma86 3x/(x+8). I need to use the 2nd derivative test to find the point(s) of inflection. I get confused about how to do derivatives of examples like this. Quotient rule If then, This should definitely be in your books/notes
So the first derivative would be -3x/(x+8)^2?
Originally Posted by akuczma86 So the first derivative would be -3x/(x+8)^2? NO. Its
Originally Posted by akuczma86 So the first derivative would be -3x/(x+8)^2? <<<<<< no Expand the bracket in the numerator, collect like terms.
Am I right here?
It is OK for f'(x) BTW an easiest way in this case is . The derivative of f is the same as the derivative of which is The derivative of is Use this formula with u(x) = x+8 and n=-2 to get the derivative of then multiply by 24
Originally Posted by akuczma86 Am I right here? <<<<<< I can't imagine how you got this result then This result is correct but nearly useless. Compare with the method posted by running-gag: then Both terms describe the same function!
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