First, we have to convert our function (of x) into a function of y (we revolve the curve around the y-axis). So:
And the derivative of x:
Now, we can calculate the area of the surface:
We could calculate this integral (not very hard, but long), or use
(1),
(2) and
(3) to get:
Calculate indefinite integral:
And the area:
![A=2\pi\int\limits_0^{10}x\sqrt{4x^2+1}\,dx=2\pi\cdot\dfrac{1}{12}\bigg[\left(4x^2+1\right)^\frac{3}{2}\bigg]_0^{10}=\\\\\\= \dfrac{\pi}{6}\left[\big(4\cdot10^2+1\big)^\frac{3}{2}-\big(4\cdot0^2+1\big)^\frac{3}{2}\right]=\dfrac{\pi}{6}\Big(\big401^\frac{3}{2}-1^\frac{3}{2}\Big)=\boxed{\dfrac{401^\frac{3}{2}-1}{6}\pi}](https://tex.z-dn.net/?f=A%3D2%5Cpi%5Cint%5Climits_0%5E%7B10%7Dx%5Csqrt%7B4x%5E2%2B1%7D%5C%2Cdx%3D2%5Cpi%5Ccdot%5Cdfrac%7B1%7D%7B12%7D%5Cbigg%5B%5Cleft%284x%5E2%2B1%5Cright%29%5E%5Cfrac%7B3%7D%7B2%7D%5Cbigg%5D_0%5E%7B10%7D%3D%5C%5C%5C%5C%5C%5C%3D%20%5Cdfrac%7B%5Cpi%7D%7B6%7D%5Cleft%5B%5Cbig%284%5Ccdot10%5E2%2B1%5Cbig%29%5E%5Cfrac%7B3%7D%7B2%7D-%5Cbig%284%5Ccdot0%5E2%2B1%5Cbig%29%5E%5Cfrac%7B3%7D%7B2%7D%5Cright%5D%3D%5Cdfrac%7B%5Cpi%7D%7B6%7D%5CBig%28%5Cbig401%5E%5Cfrac%7B3%7D%7B2%7D-1%5E%5Cfrac%7B3%7D%7B2%7D%5CBig%29%3D%5Cboxed%7B%5Cdfrac%7B401%5E%5Cfrac%7B3%7D%7B2%7D-1%7D%7B6%7D%5Cpi%7D)
Answer D.
Volume = (PI * r^2 * h) / 3
r^2 = (3 * Volume) / (PI * h)
r = Square Root (3 * Volume) / (PI * h)
Dilation- A figure that grows or shrinks but still maintains its very shape.
Answer:
30
Step-by-step explanation:
He is walking 3 dogs an hour
Answer: Edwin is likely a typo for Wesley.
Step by step:
Wmom=57
Wmom=3+2e
57=3+2e
54=2e
27=e
Edwin is 27 years old.
Aside from a typo, one can speculate on Wesley's age. He's likely between 20 and 39 years old based on his mother's age. If you want to delve into societal norms, Wesley is likely to be a name from a white middle to upper class parentage, so it's less likely he was had when his mother was a teen, or even in her early twenties because college, so move that age zone to 20 to 34. Then consider that having children later than 35 is consideration for a "risky" pregnancy and most women are urged to aim for before 33, but most upper middle class white women will be pressured to baby before 30. So, adjust Wesley's age zone to 27 to 34. And then...idk. But in all honesty I think Edwin is meant to be Wesley, because it's a math problem not a sociology one.
