- #1

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Hint: Use Euler’s formula and the geometric progression formula.

Err, I know Euler's formula, or at least a version of it, but I don't see how that helps here, so yah, how's that work, since it obviously does?

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- Thread starter schattenjaeger
- Start date

- #1

- 178

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Hint: Use Euler’s formula and the geometric progression formula.

Err, I know Euler's formula, or at least a version of it, but I don't see how that helps here, so yah, how's that work, since it obviously does?

- #2

Tom Mattson

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- #3

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ok, thanks! Now here's a good 'ol check my work question

y^3-x^2y=8, at the point (-3,1) is the slope 1 and the equation of the tangent line y=x+4?(that's what I got, I'm asking for confirmation)

EDIT: Nevermind, there was a typo in the problem on the teacher's site, 'cuz I found the same problem in the book with the point being (3,-1), which it has to be because (-3,1) doesn't solve that equation! Then the answer is y=x-4, which I checked with some cool graphy thing I downloaded. Three cheers!

and another one to get me started on

III.2: Find the largest box (with faces parallel to the coordinate axes) that can be inscribed within the ellipsoid:

(x^2)/4 + (y^2)/9 +(z^2)/25 =1

I'm assuming it's some type of lagrange multiplier problem, but I dunno...

y^3-x^2y=8, at the point (-3,1) is the slope 1 and the equation of the tangent line y=x+4?(that's what I got, I'm asking for confirmation)

EDIT: Nevermind, there was a typo in the problem on the teacher's site, 'cuz I found the same problem in the book with the point being (3,-1), which it has to be because (-3,1) doesn't solve that equation! Then the answer is y=x-4, which I checked with some cool graphy thing I downloaded. Three cheers!

and another one to get me started on

III.2: Find the largest box (with faces parallel to the coordinate axes) that can be inscribed within the ellipsoid:

(x^2)/4 + (y^2)/9 +(z^2)/25 =1

I'm assuming it's some type of lagrange multiplier problem, but I dunno...

Last edited:

- #4

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For those wondering how to do the box problem, f(x,y,z)=8xyz, and g(x,y,z)=[thatequationfortheellipse], and then it's just good 'ol Lagrange multiplier stuff, with 4 unknowns and 4 equation, which happen to solve real nicely

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