Year 12s: what will be the first way you research your future options? >>

c3 question help

Kalabamboo

Cna somebody tell me how to do ii please

Reply 1

Radioactivedecay

Find h in terms of r using trig and sub back into the volume formula. Use chain rule to find dv/dr.

Reply 2

Kalabamboo

Original post by Radioactivedecay

Find h in terms of r using trig and sub back into the volume formula. Use chain rule to find dv/dr.

so everything else makes sense -just that first part is still confusing -so just the show that V= root3/3 pir^3 bit

...

...

...

anyone? please

h, r & tan30° are connected.

express h in terms of r and tan30°... then substitute into the formula for V

Reply 8

RDKGames

Study Forum Helper

Original post by Kalabamboo

anyone? please

Not sure what you are struggling with.

V = \frac{1}{3}h \pi r^2

r=r

as normal.

\frac{r}{h} = \tan 30

h = \frac{r}{\tan 30}

Hence

\displaystyle V = \frac{1}{3} \frac{r^3 \pi}{\tan 30}

Reply 9

Kalabamboo

Ah thanks a lot :smile:

Quick Reply

Latest

Articles for you

Making the grade: A* students share their revision tips and secrets

English and history students share why they loved their degrees

Why I loved studying online

How to revise for GCSE Business exams: AQA explains what to do

c3 question help

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you