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Math Help - Making r the subject

  1. #1
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    Making r the subject

    Hey guys,

    As Im a noob at maths I need your help in making r the subject so I can figure out the radius of my nanoparticles. Can someone please help

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  2. #2
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    Hi Donut

    Mulitply both sides through by r^2

    you can then use the quadratic formula to solve for r.
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  3. #3
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    hmm thats what I thought I should do but I get keep getting this obscenely small number. Back to the drawing board I guess >_<

    Thanks for the reply

    I might post up all my previous working in a sec and see if someone can see the holes in it.
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  4. #4
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    Are the calculations right?
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  5. #5
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    If I can find out that all the above maths is correct it would be a massive help
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  6. #6
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    Take your solutions for r and sub them into the RHS of the equation. Does it give you the LHS?
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