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anonymous
 5 years ago
please help me out with this one a right circular cone has a surface area of 718 square inches. what dimensions (radius and height) will result in a maximum volume?
anonymous
 5 years ago
please help me out with this one a right circular cone has a surface area of 718 square inches. what dimensions (radius and height) will result in a maximum volume?

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I began the problem, and now it after 30 mins of work it is a nightmare.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1What class is this forcalculus?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so far, i've taken the SA eqn and tried to optimize it with substitution, but then after finding a derivative it just is bad.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1If you could find satellite of myininaya they could help you

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1is there a formula for the surface area of a rt circular cone?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1and perferably one for volume as well to relate the 2?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.11/3 something is all i can remember

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.11/3 volume of a cylinder perhaps?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1ok; looks like we are given an value for SA so that we can find an r perhaps?

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1The problem is the slant height adds a variable.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1i take it thats the "l" part in the SA

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1dw:1327287244737:dw

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1l = sqrt(h^2 + r^2) then 718 = pi r^2 + pi r(sqrt(h^2+r^2)) 718/pir = r + (sqrt(h^2+r^2)) (718/pir)  r = sqrt(h^2+r^2) [(718/pir)  r]^2 = h^2+r^2 [(718/pir)  r]^2  r^2 = h^2 i wonder of thats going according to plan :)

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1at any rate we can define h in terms of r; aint pretty but doable

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1That should be progress. Wonder where the asker is.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1fetal position, sobbing maybe lol

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1V = 1/3 pi r^2 h \[V=\frac{pi\ r^2\ \sqrt{(\frac{718}{pi\ r}r)^2r^2}}{3}\] looks about right?

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Now I suppose we have to differentiate that and set to 0?

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1the 1/3 pi is a constant that can be put to the side and we are left with deriving:\[V=r^2\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}\]

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1yep, find the zeros and the undefineds to test

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1\[V'=r'^2\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}+r^2\ ((\frac{718}{pi\ r}r)^2r^2)'^{1/2}\] \[V'=2r\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}+\frac{1}{2}r^2\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}*((\frac{718}{pi\ r}r)^2r^2)'\] \[V'=2r\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}+\frac{1}{2}r^2\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}*(\frac{718}{pi\ r}r)'^2r'^2\] \[V'=2r\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}+\frac{1}{2}r^2\ ((\frac{718}{pi\ r}r)^2r^2)^{1/2}*2(\frac{718}{pi\ r}r)(\frac{718}{pi\ r}r)'2r\] yep, its a doozie; the wolf might be quicker

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1yeah, i was gonna say around 8

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1plug that value in to get the V max

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1I just ignored the miserable denominator and set the numerator to 0.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Must first find the height

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1[(718/pir)  r]^2  r^2 = h^2 plug in yer r

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1i dunno if solving in terms of h would have been easier

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1tooooooooooooooooooooooooooooo late

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1lol, since h was buried i assume not

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1that should do it then

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Except for checking to make sure those values result in the correct surface area.

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1it has to, we did everything correctly

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Of course...no mistakes...ever!!

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1they wanted max volume

amistre64
 5 years ago
Best ResponseYou've already chosen the best response.1the wolf helped so we can always pass the blame ;)

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Good to have a scapegoat.

Mertsj
 5 years ago
Best ResponseYou've already chosen the best response.1Hey!! It's right. SA = 717.9758
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