[soze=3]Hello, dklee41![/size]
The stiffness of a rectangular beam is jointly proportional
to the breadth and the cube of the depth.
Find the dimensions of the stiffest beam that can be cut from a log
in the shape of a right-circular cylinder of radius centimeters. Code:
* * *
* *
*-------+-------*
*| : |*
| y: |
* | : | *
* | * | *
* | : \ | *
| y: \a |
*| : \ |*
*-------+-------*
* x x *
* * *
The breadth is , the depth is
Since , we have: . [1]
From the diagram we have: . [2]
Substitute [2] into [1]: .
And that is the function we must maximize . . .