Help with a math question?

Question

I only have a question. I am doing my math homework and a question says: Express the Volume (V) of the cylinder as a function of radius (r).
Does this mean that I have to solve for the radius (r)?
Thank You!

Answer 1

The volume of a cylinder is the area of a circle times the height of the cylinder.

Let V = Volume
Let r = Radius of the cylinder
Let L = Length of the cylinder

V = π * r * r * length

V= π * r^2 * L

Putting it into function notation

V(r) = π * r^2 * L

Answer 2

Volume as a function of radius means the Volume stands alone at the beginning, and radius appears in the formula. So you solve for V, not r. However, no other variable may appear in the formula. So you can't , say, write V = pi r^2 h
You'd have to see what h is in terms of r also. Does it say that height equals twice the diameter or something you can use to do this?

Answer 3

If the cylinder has a length (or height) L, then the volume is

pi X r^2 L

where r is the radius

Answer 4

volume of a cylinder
round like a circle - with height

so what is the formulae for area of a circle???????

then times h (height)

pie R squared x h = vol of cyl

no no no - cornbread are squared - pie r round!

oh well you know now - and u won't forget

radius = 1/2 diameter

if you know volume and height - - - - - - - -u can find the radius

volume divided by height divided by pie = radius squared

that's just the formulae spread out the other way

all the best !

Answer 5

No, you just state the formula as V(r) = pir^2h. Hopefully you know h so you can put that number in and then the only variable is the r

Answer 6

simply make r the subject of formular
i.e
if the volume is
V = π * r ^2 * L
then
r^2=V/(π *L)
r=sqroot(V/(π *L))
enjoy

Answer 7

Like everyone has already mentioned... V(r) = pir^2h