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If (cgt 0) and 2ax^2+3bx+5c=0 does not h...

If `(cgt 0)` and `2ax^2+3bx+5c`=0 does not have any real roots, then prove that `2a-3b+5c gt 0.`

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`f(x) = 2ax^2+3bx+5c`
As, D of `f(x) lt 0` Now `f(0) =5c(gt0)`, so f(x) positive, therfore `f(-1) gt 0`
`implies 2a-3b+5cgt0 ` Hence proved
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