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    [QUOTE=MathsAssist;73835600]I'm having trouble understanding why an indices rule "simplification" does not work as I attempted it in regards to this question:

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    would you simplify (9-x)^2 as 9^2 - x^2 ?
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    (Original post by ckfeister)
    The chain rule?



    \int^3_0 (9 - x^2)^1^/^2)  dx

    \int (9-x^2)^1^/^2  dx

    u =  9-x^2
    y =  u^1^/^2


    Chain rule:
    dy/dx = du/dx . dy/du

    https://www.youtube.com/watch?v=DhUCSxZbtCM
    That's completely wrong. The chain rule is for differentiation. Also yeah op you simplified it wrong.
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    (Original post by black1blade)
    That's completely wrong. The chain rule is for differentiation. Also yeah op you simplified it wrong.
    I said the wrong one, meant du thing, thx for saying...
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    Actually yeah I'm fairly sure this is far beyond a core 2 integral, probably a typo. If the whole thing was raised to a positive integer power you could do it.
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    And yeah in terms of the simplifaction (9-x^2) factors into (3+x)^0.5(3-x)^0.5
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    (Original post by black1blade)
    Actually yeah I'm fairly sure this is far beyond a core 2 integral, probably a typo. If the whole thing was raised to a positive integer power you could do it.
    It could be C2 if there was guidance from the question - this is the equation of a circle so using a sketch and \pi r^2 you can work it out.
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    (Original post by univ4464)
    It could be C2 if there was guidance from the question - this is the equation of a circle so using a sketch and \pi r^2 you can work it out.
    Ah yes of course circle centered on the origin with radius 3.
 
 
 
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