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If a ,b ,c in R^+t h e n(a+b+c)(1/a+1/b...

If `a ,b ,c in R^+t h e n(a+b+c)(1/a+1/b+1/c)` is always `geq12` `geq9` `lt=12` none of these``

A

`ge 12`

B

`ge 9`

C

`le 12`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
`(a + b + c)/(3) ge (3)/((1)/(a)+ (1)/(b) + (1)/(c ))` ` ( :' A.M ge H.M)`
or `(a + b + c) ((1)/(a) + (a)/(b) + (1)/(c )) ge 9`
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