<span>Let r(x,y) = (x, y, 9 - x^2 - y^2)
So, dr/dx x dr/dy = (2x, 2y, 1)
So, integral(S) F * dS
= integral(x in [0,1], y in [0,1]) (xy, y(9 - x^2 - y^2), x(9 - x^2 - y^2)) * (2x, 2y, 1) dy dx
= integral(x in [0,1], y in [0,1]) (2x^2y + 18y^2 - 2x^2y^2 - 2y^4 + 9x - x^3 - xy^2) dy dx
= integral(x in [0,1]) (x^2 + 6 - 2x^2/3 - 2/5 + 9x - x^3 - x/3) dx
= integral(x in [0,1]) (28/5 + x^2/3 + 26x/3 - x^3) dx
= 28/5 + 40/9 - 1/4
= 1763/180 </span>
For the most part, the cross-section formed is a <em>trapezoid</em>, but if the slice passes through the apex of the pyramid, that shape is a <em>triangle</em>.
(Image source: MathCaptain.com)
Hi!
The answer to your question is 9.75 minutes
Here is the math to prove it:
9+11+3+14+14+7+14+6=78
Now you will take 78 and divide it by 8
This is because when finding the mean you add all of the given number together and then divide them by the amount of number added together.
78/8=9.75
Thus, your answer is 9.75 minutes
I hope this helped!
Have a wonderful day/night!
God bless!
Answer:
i thinks the answer is the fourth, which an= 3-2(n-1)