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#1 2014-04-18 01:28:45

gourish
Member
Registered: 2013-05-28
Posts: 153

functions #2 related to geometry

a cylinder is inscribed in a sphere of radius R. the volume V of the cylinder is written as V=f(x) where x is the height of the cylinder
find the function with it's domain and range. when is it maximum and when is it minimum?


"The man was just too bored so he invented maths for fun"
-some wise guy

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#2 2014-04-18 03:23:03

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: functions #2 related to geometry

hi gourish,

Once again, I've made a diagram with the height 'on its side' so that x is across.

If the cylinder is height x, then the centre of the sphere is at (½x,0) and you can use Pythagoras to get y, the radius of the cylinder, in terms of x and R.  Is that enough to get you to an answer?

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#3 2014-04-19 18:04:30

gourish
Member
Registered: 2013-05-28
Posts: 153

Re: functions #2 related to geometry

smile thanks again bob you make them look so simple with the diagrams.


"The man was just too bored so he invented maths for fun"
-some wise guy

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