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How do i solve this equation?? C2

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    4x-480x^-2=0
    howq do i solve? step by step? Thanks all!
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    try multiplying by x^2
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    (Original post by Coulson72)
    try multiplying by x^2
    Okay sweet I got : 4x^3-480=0
    4x^3=480
    x^3=120
    x= 3 root 120 = 4.9...
    Thanks alot btw, but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
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    well if you get summit similar try multiplying by enough to turn the biggest negative into a 0, so like if you have 2x^2+5x^-3=0 then you'd try multiplying by x^3 to turn the -3 into a 0
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    (Original post by alex7892)
    Okay sweet I got : 4x^3-480=0
    4x^3=480
    x^3=120
    x= 3 root 120 = 4.9...
    Thanks alot btw, but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
    Well it's better to get rid of the fractions or negative power (by this I mean \dfrac{1}{x^2} or x^{-2}). So multiply by whatever you need to get rid of the negative power.
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    Thanks all great help. Love feeling confident about maths and getting it haha!!
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    (Original post by alex7892)
    Okay sweet I got : but how do I choose what to multiply by if this was another q in an exam with different multiples...? Thanks though!!
    Suppose you have been given permission to drive your friends car. You are given a large bunch of keys. How do you KNOW which key to use?

    What would you do? I guess most people would try one key, then another and so on.

    It's the same with mathematics. JUST try and see what happens.

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