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Help with frustum question please watch

1. Our teacher has set the class this question as a bit of extension work. We are doing Core 1, Core 2 and Mechanics 1.

I am looking for help where to start as we didn't do much with frustums at GCSE.
2. make it into a big cone... by replacing the little cone which was cut off ? call the little cone height h.

the big cone height is thus h + 2

we can say that h/q must be the same as ( h + 2 ) / p...

now you can find an expression for h in terms of p and q.

now make expressions for the little cone volume and the big cone volume in terms of p and q.

find the difference, simplify , job done.
3. (Original post by the bear)
make it into a big cone... by replacing the little cone which was cut off ? call the little cone height h.

the big cone height is thus h + 2

we can say that h/q must be the same as ( h + 2 ) / p...

now you can find an expression for h in terms of p and q.

now make expressions for the little cone volume and the big cone volume in terms of p and q.

find the difference, simplify , job done.
Thanks

I got that far but it leaves a mess and I can't get the answer shown.
4. you need to factorise & simplify...

i am not allowed to furnish all details

PS the fraction k is irrational
5. Got that far but can't simplify
6. (Original post by peter104)
Got that far but can't simplify
can you post what you have got so far ?

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