How to Find the Volume of a Cone Using Integration?

[rainbowGirl]

Can anyone help me with this question?

A uniform solid cone of height b and base radius a stands on a horizontal table. Find an expression for the volume of the disc at height h above the base. Integrate over all the discs to show that the total volume, V, is given by V =pi/3 * b * a^2

 

[NateTG]

Can you find the radius of the cone at height h?
What is the volume of a cylinder with radius r and height dx?

 

[Tide]

You might find this thread useful: https://www.physicsforums.com/showthread.php?p=341886#post341886