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प्रश्न
If V is the volume of a cuboid of dimensions a, b, c and S is its surface area, then prove that
`1/V=2/S(1/a+1/b+1)`
उत्तर
Given that
Length = a
Breadth = b
Height = c
Volume `(v)=lxxbxxh`
`=axxbxxc=abc`
Surface area `2(lb+bh+hl)`
`=2(ab+bc+ac)`
`Now , 2/5[1/a+1/b+1/c]=2/(2(ab+bc+ca)) [[ab+bc+ca]]/(abc)`
`1/(abc)=1/v`
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