Find the numberssuch that the average value of f(x) = 2+6x-3x^2 on the interval [0,b] is equal to 3b

I am stuck atb^2(3-b)=band don't know what to do. Or I am doing something wrong ?

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- Jan 31st 2010, 08:09 AMracewithferrariFinding the upper limit of the integral
Find the numbers

such that the average value of f(x) = 2+6x-3x^2 on the interval [0,b] is equal to 3*b*

I am stuck at**b^2(3-b)=b**and don't know what to do. Or I am doing something wrong ?

Attachment 15131 - Jan 31st 2010, 08:18 AMPlato
Just solve $\displaystyle b^3-3b^2+b=0.$

- Jan 31st 2010, 08:22 AMracewithferrari
Oh!!! Thanks I didnt realize that

- Jan 31st 2010, 08:55 AMracewithferrari
So my answer is coming in decimals,is it ok...?

- Jan 31st 2010, 09:04 AMPlato