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Math Help - inflection points Please help URGENT! class about to start

  1. #1
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    inflection points Please help URGENT! class about to start

    Find the inflection points of (x+2)(x-4)^2

    i found the second derivative which is very long

    2(x-4)2(x-4)(x+2)+(x-4)^(2)*2(x+2)+2(x-4)=0

    I got one inflection point which is 4 but there must be others cause my online hw says its wrong
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  2. #2
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    I get something quite different for the second derivative. Please reply showing your steps. Thank you!
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  3. #3
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    Quote Originally Posted by Asuhuman18 View Post
    Find the inflection points of (x+2)(x-4)^2

    i found the second derivative which is very long

    2(x-4)2(x-4)(x+2)+(x-4)^(2)*2(x+2)+2(x-4)=0

    I got one inflection point which is 4 but there must be others cause my online hw says its wrong
    I don't know how you calculated the second derivative, but that answer is very wrong. The easiest way to differentiate (x+2)(x-4)^2 twice is probably to multiply it out first: (x+2)(x-4)^2 = (x+2)(x^2-8x+16) = x^3 -6x^2 +32. That should be easy to differentiate.
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