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Completely stuck on this Maths question!! NEED HELP!! watch

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    Name:  photo.jpg
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    Well, brute forcing it is surely possible.

    1. Find y=f(x)
    2. Find y=g(h)
    3. f(x)=g(h) then get h by itself.
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    (Original post by SpacVelociraptor)
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    Write out the volumes. It should be easy to see how you can eliminate y.
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    It's better to show your attempts and allow people to point out errors, rather than have someone come along and give you the answer. But I'm sure you'll get there
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    (Original post by SpacVelociraptor)
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    HINT: the volume of a cone is 1/3 the volume of a cylinder with the same height and radius.
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    Write out the volumes of each shape (maybe called the spheres 1 and 2 as they are separate).
    Eg. cylinder is pi x r^2 x h

    Then plug in the relevant substitutions. Eg for the cylinder, the radius (r) is 2y. And so on.

    You'll come to 4 volumes for each shape each in terms of y.

    Put the correct volumes equal to one another. (Cylinder volume equal to sphere 1 etc).

    Get y= for both.

    Solve and you should get h=Ax, with A being a number people can confirm once you've given it a go.
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    I remember doing this question for my GCSE maths exam!
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    This is as far as I get before I get completely stuck! Name:  photo (1).jpg
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    (Original post by SpacVelociraptor)
    This is as far as I get before I get completely stuck! Name:  photo (1).jpg
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    r= 3y \Rightarrow r^2 = (3y)^2 \neq 3y^2

    same for 2y.

    So you have

    \pi (2y)^2 x = \frac{4}{3}\pi(2y)^3

    and

    \pi (3y)^2 h = \frac{4}{3}\pi(3y)^3
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    Hint:

    Divide the top equation through by

    \pi(2y)^2
 
 
 
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