Melody

I started with 

\(f(x)=ax^3+bx^2+cx+d\)

d is super easy to find

then I formed simultaneous equations  which will be used to find a,b and c

  You do this by substitution

and then solved them using matrices. 

Do what you can and get back to us - show us what you have done.

I already answered this.

If you are not happy with the answer say so on the original thread.

Please give the address of the original post.

That is a neat answer Jugoslav.   

Thanks, I was having a mental block.   ​

The only thing you forgot is that it has to be shown that AB has a perpendicular distance to (0,0) of 3 units.

This is not hard to do, you can just use the Pythagorean triad 3-4-5  but it does have to be shown before your part of the calculations.

Yes that is what I got too.  I might show my answer now.

Guest answerer did help you.  It is a pity you still have not acknowledged that.

I haven't worked out how to do it with theoretical geometry and Algebra.

But here it is drawn to scale.

The radius is approx (maybe exact)  0.75

so the area is  approx  0.5625pi  cm^2

Yes you are right.

One of the answers is correct.

Now the answerer has given you a technique that you say you understand.

And he/she has given you one correct answer.

That correct answer makes it easier for you to solve it by yourself.  (I know because i have solve it)

So you have a technique and a correct answer.

Seems to me that the guest answerer has helped you are real lot!

Which one.  I am sure the answerer would like some positive feedback from you.

The respondent does not need to check their answer if they do not want to.

It is up to the asker to accept, reject or alter an answer as they feel the need.

The asker should at the very least check answers by substitution if that is possible.

The respondents are here to offer their help or suggestions.

It is not the respondent's job to give polished answers that can be copied without thought.