If `a x+b/xgeqc` for all positive `x` where `a ,\ b ,\ >0` , then `a b<(c^2)/4` (b) `geq(c^2)/4` (c) `a bgeqc/4` (d) none of these

Explanation

Let `{f}({x})={ax}+\frac{{b}}{{x}}-{c} ; {x}>0 ; {a}, {b}>0`


`\Rightarrow {f}^{\prime}({x})={a}- `


`{f}^{\prime}({x})=0 `



`\Rightarrow {a}-\frac{{b}}{{x}^{2}}=0 `
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