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Help!! Maths question help needed Watch

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    Hey I'd really appreciate help with this question please I really can't remember how to do it! Is f(x)=9-(x-2)^2 write down the maximum value of f(x) please leave working out too Thankyou!!!
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    (Original post by Sukjeetsandhu)
    Hey I'd really appreciate help with this question please I really can't remember how to do it! Is f(x)=9-(x-2)^2 write down the maximum value of f(x) please leave working out too Thankyou!!!
    complete the square

    (x-a)^2=b

    then max/min is at (a,b)
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    (Original post by Sukjeetsandhu)
    Hey I'd really appreciate help with this question please I really can't remember how to do it! Is f(x)=9-(x-2)^2 write down the maximum value of f(x) please leave working out too Thankyou!!!
    Why would I leave working out? Have a go at it yourself.

    It's a quadratic so it's when (x-2)^2=0 so you're not subtracting anything. You can sketch the thing anyway and see it.

    Otherwise differentiate it, solve it for x, and plug the solution back through the function.
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    (Original post by KloppOClock)
    complete the square
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    Pssst.... it's already IN a completed square form :teehee:
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    (Original post by RDKGames)
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    Pssst.... it's already IN a completed square form :teehee:
    oh yeah, i just uncompleted it and then recompleted it lol
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    (Original post by KloppOClock)
    complete the square

    Set f(x)=0

    0=9-(x-2)^2
    =9-(x^2-4x+4)
    =9-x^2+4x-4
    =5-x^2+4x
    x^2-4x=5
    (x-2)^2-4=5
    (x-2)^2=9

    So max is at (2,9)
    lol
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    (Original post by Zacken)
    lol
    shh i edited it, no one saw that
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    (Original post by KloppOClock)
    shh i edited it, no one saw that
    It's still in the quote
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    ...and why did you make it equal to 0? No need, you're not finding roots
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    (Original post by RDKGames)
    It's still in the quote
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    ...and why did you make it equal to 0? No need, you're not finding roots
    lmao i need coffee
 
 
 
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