Very tough problem

[Ajinkya Jumbad]

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Solve the question no. 14, it is tough , i tried for days but did not get it.

 

[-Hatake-]

Quite difficult.

 

[Ogracio]

One question, are they semi circles or functions?

 

[Akuma]

Dang, confusing.

 

[Ogracio]

nvm me, they are semi circles, let me try and solve it with integrals.

 

[Illyasviel]

It's not hard at all
It's the basic maths knowlage of the 7th grade of the primary school(13 years) here.

 

[Dr Strangelove]

?????????

 

[Iceblade805]

It's not hard at all
It's the basic maths knowlage of the 7th grade of the primary school(13 years) here.

it's not that difficult just the function of semi-circels and integrals, but 13 is a bit young, here we could do it at 16/17 years old..

 

[Illyasviel]

it's not that difficult just the function of semi-circels and integrals, but 13 is a bit young, here we could do it at 16/17 years old..

Yes we learned so much things in the 7th grade and I don't remember almost anything now in the eight grade

 

[mistype]

16.746cm²

 

[Ajinkya Jumbad]

Do you have the answers? or someone who does? I got 27.7128

i dont know the answer, i want the working of it.

 

[mistype]

π • 8cm = 25.12cm
25.12cm : 12 = 2.093cm
4 • 2.093cm : 2 = 4.186cm²
4.186cm² • 4 = 16.74cm²

Or just π • 4² : 3

 

[Ogracio]

i got a different answer, and the real one (by two methods) which is 19.6539.

Easy method, there is a formula, which is (((4*pi)+(3*sqr(3)))/6)*r^2.
or the hard method which involves integrals, which is the integral from -3.4641 to 3.4641 or sqr(12) , of the following equations:
y1 = sqr(16-X^2) y2= 4 - sqr(16-x^2)

so you evaluate the integral from those limits, and the difference between y1-y2.