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anonymous
 5 years ago
Find the area of the largest rectangle with a base on the positive x axis, its right side on the line x=9 and which is inscribed under the curve f(x) = root(x)
anonymous
 5 years ago
Find the area of the largest rectangle with a base on the positive x axis, its right side on the line x=9 and which is inscribed under the curve f(x) = root(x)

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I don't get it... can anybody help please?

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1you have to integrate on root(x) from x=0 to x=9.

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1actually that doesn't give you a rectangle. hmmm....

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1this is the graph. it is strange though because at x=0, y = 0

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0screen shot is nothing

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, i can't see anything

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1you have to find the largest rectangle possible. looking at the graph i would guess (4,2) but that's just a though....

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0apparently we have to do it through optimization  derivatives and all that fun stuff

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0This is one of those questions you ask an instructor whose got over 20 yrs cal experience.

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1find a function for the area of the square and optimize. the area of the square at a given x up until 9 = x*y = sqrt(x) * (9x)

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1try deriving that and see if find an extrema

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0not really :) as long as you have the skill then it's no prob

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it's one of those questions that are a challenge ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0loving the enthusiasm sstarica, but i'm getting mercilessly owned in cal a

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0LOL, nah, let it be the opposite. It's quite simple, believe me :)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0logically, I'd say the following: since the lenght of the rectangle is = 9, and is under the sqrt(x) now, let's first draw sqrt of (x) and notice that when you take x = 9, you'llhave y = 3. Logically, the rectangle won't exceed this limit, so the width is equal = 3

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2matt has ir right! good job

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0since it's inscribed under it

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1yes the maxima of that graph is 3!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0:) no need for all this.

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2now we need to find A'

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0all you had to do is draw sqrt(x) and see the limit of the rectangle. ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why A'? doesn't he want A?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0A = 3 x 9 = 27 that if he asked for A right? ^_^

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2to maximize you find A'

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2yes x=3 is right matt thats are only critcal number thats in the domain of A

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0wait wait, why is 9=xy? doesn't A=xy?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0since he wants the largest area, then yes maximize, proceed matt and hope you understood what was going on Ire :)

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2i didnt see A=9 up there no

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0you want the largest area, so you have to maximize in this case, they didn't ask for the "area" alone, but largest one

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1right. to find where the area is a maximum, take a function for the area and find the maxima point. take that point to make your rectangle. since you go up to 9 the x width is (93) = 6. the height of the rectangle is sqrt(3)

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0could you remind me how to find the maxima point please?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0which means "optimize" lol, alight matt will take it from here ^_^ good luck

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1take the derivative of the area function 'A'. find where the derivative = 0.

mattfeury
 5 years ago
Best ResponseYou've already chosen the best response.1normally, you'd have to do the second derivative test to find out if it is a max/min too. but i know secrets.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.01. A = (9x) * sqrt(x)

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2also i never use the second derivative test it is pointless you can use A' to see if it is increasing to decreasing at x=3 to find that it is a max

myininaya
 5 years ago
Best ResponseYou've already chosen the best response.2The first derivative rocks!

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0thanks for the help guys, really appreciated
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