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LaddiusMaximus
 2 years ago
Find the dimensions of the rectangle of maximum area that can be formed from a 330in. piece of wire
LaddiusMaximus
 2 years ago
Find the dimensions of the rectangle of maximum area that can be formed from a 330in. piece of wire

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cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2so we have a rectangle dw:1334016584546:dw A = b * h and we know that b + h = 330 inches Follow?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Now we need to solve for one of the variables b = (330  h) thus A = (330  h)h How about a little interaction :l

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0so is that a standard formula?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2This is normally what you do yes

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0Sorry my son is crying.

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0is that all there is to it?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2So next step we need to take the derivative with A respect to the change in x so (Ad/dx) A = (Ad/dx) 330h  h^(2) A' = 330  2h

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Now We need to look at the domain of A' = 330  2h and see if we can find any places where it violates the domain (as this could be a place where the graph changes) The domain is clearly all real numbers Next We set A'(x) = 0 (write this on your test it looks good and will get you a mark probably) 330  2h = 0 Now solve

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Do you follow so far?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2btw there is no standard formula but we know: Area of a Square (or Rectangle) = Base * Height We also know that the length of the wire is all sides added up so we get b + h = Length of wire or we could express it as 2b + 2h = Length of wire But really that would give you the same answer its best to keep it simple

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2h = 165 so we have a point Now we need to use the rules MEMORIZE THESE BTW f'(x) > 0 The function is increasing f'(x) < 0 The function is decreasing Make a Table dw:1334017324830:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2sub a number smaller than 165 and a number larger than 165 into the function A'(x) = 330  2h

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Do this on your test for more marks :)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2then check to see if it is positive or negative and put it in the square of the chart

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Keep it simple !!! I would go 330  2(0)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2= 330 this is positive f'(x) > 0 Function is increasing so dw:1334017519222:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Remember you can use any number smaller (unless it is not defined by the domain) :)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Fill in the next part of the chart :)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2hell I will do it I should be studying General intermediary metabolism :) FML dw:1334017660396:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2yup you can tell that the function will give you a negative number right 330  2(166)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2thus you can deduce that your graph looks something like thisdw:1334017724724:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Can you now see the answer? h = 165 So now we know the max size of the height to give optimial area Can you guess how to solve for the base?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2do you follow? If you dont understand something ask

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0do i use base times heighy?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2dw:1334017945453:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2No think about what you are doing, go back to the original formulas Calculus is just measuring change. With these problems we just are measuring how the Area changes when we change the length of h

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Area of a rectangle = base * height Length of The wire = Height length + Base length A = b * h and we know that b + h= 330 inches If we know that base length is = 165 and total wire used is = 330 165 + b = 330

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2solve for b to find the length of the base

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.00h 330165. sorry Im way behind in this class. Its been a rough semester.

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Do you see how obvious the answer is :) I hear you, I'm probably going to fail some of my classes :(

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Remember when deal with these questions though always take into consideration each side of the object

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2so what would the actual lengths of h and b, be

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2I even explained how to get the final question earlier on lol. Think about it

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2you have b= 165 inch and h = 165 inch and you have a 4 sided rectangle

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2I went a little more of an indirect route because it kept the arithmatic simpler

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2The actual formula would be 2b + 2h = A you cant make a 4 sided object with only 2 strands of wire

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2165/2 = 82.5 inches dw:1334018556160:dw

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2To get the max area of a rectangle all sides have to be the same length :)

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2sorry for over complicating it but you would get the same answer if you used 2b + 2h = Area

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.082.5 is not right either.

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2To maximize the area of a rectangle all sides must be of equal length

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0dimension of maximum area? 82.5 in^(2)?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2yes you probably forgot units

LaddiusMaximus
 2 years ago
Best ResponseYou've already chosen the best response.0it doesnt require me to enter units

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2well I recommend email the people overseeing your course, but lets ask someone to check first

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Someone else on the site

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2The answer I got is h = 82.5 and b = 82.5

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2You sadisfied Laddius?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2do you understand the process?

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Trust me it is right, logically it makes sense

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2Its easy 1st acquire two formulas from the question 2nd Solve for one of the variables in one of the equations and sub it into the other equation 3rd take the derivative of the new equation you made 4th check domain and points the function is 0 5th look to see if function is increasing or decreasing and at what point it is at its max or min and that will be your answer 6th sub the answer back into the one of the equation to solve for the other variable. 7th check to see if your answer is reasonable

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2The answer would be 85.5*85.5 or the Max Area sorry

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2the real answer would be 7310.25

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2sorry that is the answer I'm not use to using a calculator for these kinds of questions

cuddlepony
 2 years ago
Best ResponseYou've already chosen the best response.2try it I bet it works
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