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    I need some help with rearranging some equations I got for my homework on enrolment day to college.

    1.Make “x” the subject of E = ½ k x2
    2.Make “G” the subject of V = -GM/r
    3.Make “k” the subject of T = 2*pie√(m/k)
    4.Make g the subject of T = 2√(l / g)
    5. Make “C” the subject of f =1/2*pie√ (LC)
    Thanks in advance ( some working would be appreciated)
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    (Original post by kszyni1)
    I need some help with rearranging some equations I got for my homework on enrolment day to college.

    1.Make “x” the subject of E = ½ k x2
    2.Make “G” the subject of V = -GM/r
    3.Make “k” the subject of T = 2√(m/k)
    4.Make g the subject of T = 2√(l / g)
    5. Make “C” the subject of f =___1____
    2√ (LC)
    Thanks in advance ( some working would be appreciated)
    you just undo one thing at a time e.g.

    1.
    E = 1/2 k x2 (assume that's meant to mean squared)
    x 2
    2E = k x2
    divide by k
    (2E)/k = x2
    square root
    √ 2E/k = x

    so for number 2 you need to get rid of /r first (so multiple by r) then get rid of xM then get rid of your negative
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    ok thanks a lot but I'm not too sure how I am supposed how to do the last one but I've got all the other one done but I'm stuck on the last one don't know to work it out. help with the last one please?
    (Original post by doodle_333)
    you just undo one thing at a time e.g.

    1.
    E = 1/2 k x2 (assume that's meant to mean squared)
    x 2
    2E = k x2
    divide by k
    (2E)/k = x2
    square root
    √ 2E/k = x

    so for number 2 you need to get rid of /r first (so multiple by r) then get rid of xM then get rid of your negative
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    (Original post by kszyni1)
    I need some help with rearranging some equations I got for my homework on enrolment day to college.

    1.Make “x” the subject of E = ½ k x2
    2.Make “G” the subject of V = -GM/r
    3.Make “k” the subject of T = 2√(m/k)
    4.Make g the subject of T = 2√(l / g)
    5. Make “C” the subject of f =___1____
    2√ (LC)
    Thanks in advance ( some working would be appreciated)
    I'm not sure of how you've written the last one? waht are the underscores and where is the 1root(LC) meant to be? is it meant to be 1/(2root(LC))? if so

    f = 1/(2root(LC))
    x (2root(LC))
    f(2rootLC) = 1
    divide by F
    2root(LC) = 1/f
    divide by 2
    root(LC) = 1/2f
    square
    LC = (1/2f)^2
    divide by L
    C = ((1/2f)^2)/L

    hope that makes sense as I haven't copied the proper symbols in
    generally the approach with the more complicated ones is the same, even if you can't see the whole method straight away think 'what can I do?' so in this case the most logical think was to get rid of what was on the bottom of the fraction on the right side and once that happened it was fairly straightforward
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    Oops sorry my bad it didn't copy correctly sorry my bad.
    f = 1 / 2*pie symbol*√ (LC)
    sorry again it didn't copy the pie symbol for some reason :/


    (Original post by doodle_333)
    I'm not sure of how you've written the last one? waht are the underscores and where is the 1root(LC) meant to be? is it meant to be 1/(2root(LC))? if so

    f = 1/(2root(LC))
    x (2root(LC))
    f(2rootLC) = 1
    divide by F
    2root(LC) = 1/f
    divide by 2
    root(LC) = 1/2f
    square
    LC = (1/2f)^2
    divide by L
    C = ((1/2f)^2)/L

    hope that makes sense as I haven't copied the proper symbols in
    generally the approach with the more complicated ones is the same, even if you can't see the whole method straight away think 'what can I do?' so in this case the most logical think was to get rid of what was on the bottom of the fraction on the right side and once that happened it was fairly straightforward
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    (Original post by kszyni1)
    Oops sorry my bad it didn't copy correctly sorry my bad.
    f = 1 / 2*pie symbol*√ (LC)
    sorry again it didn't copy the pie symbol for some reason :/
    that doesn't change much, you're not solving the equation you're just making a certain thing the subject

    so if it's 2pie rather than just 2... on the step where you divide by 2, divide by 2pie and take them out together so it would be 2*pie*f
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    Ok thank you very much thanks for the great help
    (Original post by doodle_333)
    that doesn't change much, you're not solving the equation you're just making a certain thing the subject

    so if it's 2pie rather than just 2... on the step where you divide by 2, divide by 2pie and take them out together so it would be 2*pie*f
 
 
 
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