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C1: Differentiation: Help! Watch

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    Differentiate with respect to x:

    6x² - 1
    ______
    2?x


    "?" mark is a square root symbol, i.e. the denominator is 2 root x

    Any ideas?

    Thanks!
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    Quotient rule.
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    You could use the quotient rule, or because this is c1, could you not just split the numerator (so each part is over 2rootx) and then simplify each term and then differentiate?
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    I got 9/4x^1/2 + 1/4x^-3/4.
    Is that right answer? If so I know how its done?
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    \frac{6x^2-1}{2\sqrt{x}}

    Simplifies to:

    (6x^2-1)(2\sqrt{x})^{-1}

    \frac{1}{2}(6x^2-1)(x^{-\frac{1}{2}})

    \frac{1}{2}(6x^{\frac{3}{2}}-x^{-\frac{1}{2}})

    3x^{\frac{3}{2}}-\frac{1}{2}x^{-\frac{1}{2}}

    And then it should be easy to differentiate
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    (Original post by Jamil1987)
    I got 9/4x^1/2 + 1/4x^-3/4.
    Is that right answer? If so I know how its done?
    Yes, that is right.
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    (Original post by chrypton)
    Yes, that is right.
    (Original post by Jamil1987)
    I got 9/4x^1/2 + 1/4x^-3/4.
    Is that right answer? If so I know how its done?
    Surely it's

    9/2x^1/2 + 1/4x^-3/2

    ?
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    (Original post by Ryaaaaannnnn)
    Surely it's

    9/2x^1/2 + 1/4x^-3/2

    ?
    Yeah, I'm sorry you're right now. I thought the 4 was a 2.
 
 
 
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