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If f (x)=a ln |x| +bx^(2) +x has extrema...

If `f (x)=a ln |x| +bx^(2) +x` has extremas at `x=1and x=3` then:

A

`a =3/4, b=-1/8`

B

`a=3/4, b=1/8`

C

`a=-3/4,b =-1/8`

D

`a=-3/4, b=1/8`

Text Solution

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The correct Answer is:
C
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