The strength of a beam varies as the product of its breadth and square of its depth. Find the dimensions of the strongest beam which can be cut from a circular log of radius `adot`

Explanation

`b^2/4+d^2/4=a^2`

`d^2=4a^2-b^2`

`(dS)/(db)=b(-2b)+(4a^2-b^2)`

`=-2b^2+4a^2-b^2`

`=4a^2-3b^2=0`

`b^2=4/3a^2`

`b=pm2/sqrt3`

`d^2=4a^2-b^2`

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