1.

If a,b,c are non-zero real numbers, then the minimum value of the expression `((a^(8)+4a^(4)+1)(b^(4)+3b^(2)+1)(c^(2)+2c+2))/(a^(4)b^(2))` equalsA. 12B. 24C. 30D. 60

Answer» Correct Answer - C
Let `P=((a^(8)+4a^(4)+1)(b^(4)+3b^(2)+1)(c^(2)+2c+2))/(a^(4)b^(2))`
`(a^(4)+4+(1)/(a^(4)))(b^(2)+3+(1)/(b^(2))){(c+1)^(2)+1}`
`:.a^(4)+4+(1)/(a^(4))ge6,b^(2)+3+(1)/(b^(2))ge5 " and "(c+1)^(2)+1ge 1`
`[:. x+(1)/(x)ge2 " for "xgt0]`
`:.P ge 6*5*1=30 implies Pge30`
Hence, the required minimum value is 30.


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