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The expression a^2x^2+bx+1 will be posit...

The expression `a^2x^2+bx+1` will be positive for all `x in R` if

A

`b^2gt4a^2`

B

`b^2lt4a^2`

C

`4b^2gta^2`

D

`4b^2lta^2`.

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