12B-57. A company produces custom square tiles of side dimension a inches.
The cost per tile is C tile= (a - 6in)^2/(10in^2) + $2. Calculate the tile side dimension a which
minimizes the total cost of t iling a large room.
Cant figure out, coach cant figure out. answer is like 9.33
just realized the bottom is square in. and the top isnt, does that matter
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Quick help please
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Quick help please
by robertkoepl » Thu Apr 19, 2012 7:46 pm
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Re: Quick help please
by Shawn » Thu Apr 19, 2012 8:09 pm
57) Min/Max so calculus
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
Find derivative set to zero to minimize it:
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
A note for understanding: The cost per tile is the function given, but the area covered varies, so in order to properly do the problem you have to divide cost by area to get cost/area (this is what needs to be minimized not cost/tile, which is what you would get if you didn't divide). Feel free to post again if you don't understand my solution or if you have another question.
Edits: Annoying latex.
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
Find derivative set to zero to minimize it:
[unparseable or potentially dangerous latex formula]
[unparseable or potentially dangerous latex formula]
A note for understanding: The cost per tile is the function given, but the area covered varies, so in order to properly do the problem you have to divide cost by area to get cost/area (this is what needs to be minimized not cost/tile, which is what you would get if you didn't divide). Feel free to post again if you don't understand my solution or if you have another question.
Edits: Annoying latex.
Last edited by Shawn on Thu Apr 19, 2012 8:35 pm, edited 4 times in total.
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Re: Quick help please
by BlasianAsian » Thu Apr 19, 2012 8:11 pm
Yeah, one more thing. How would you find the derivative of a function with x in the denominator?
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Re: Quick help please
by nsguy1350 » Thu Apr 19, 2012 8:16 pm
2013 District 1/Region:
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
NS - 319/355
MA - 340/332
CA - 294/287
SC - 344/292
CS - 212/124 (fail)
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Re: Quick help please
by Shawn » Thu Apr 19, 2012 8:28 pm
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Re: Quick help please
by robertkoepl » Fri Apr 20, 2012 9:59 am
What do I do after that cuz I'm still getting 6
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Re: Quick help please
by Shawn » Fri Apr 20, 2012 10:53 am
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Re: Quick help please
by robertkoepl » Fri Apr 20, 2012 4:01 pm
Oh wow. You're definitely right. Thanks!!!
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