Lecture Note Function of Two Variables
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19 At a certain factory, the daily output is QKL( ,60)= K L12 13units, where K
denotes the capital investment and L the size of the labor force. Use calculus to
estimate the percentage by which the daily output will change if capital
investment is increased by 1 percent and labor by 2 percent.enAÉeragcRkmYy outputRbcaMéf¶kMNt;edayGnuKmn_QKL( ,60)= K L12 13Ékta EdlKKWCa
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2 PaKry.
20 Find the critical points of the given functions and classify them as relative
maxima, relative minima, or saddle points.
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a. f()xy,5= −−x y^22
b. f()xy,23=−x^2 y^2d. ()88
fxy xy,
x y= ++
e. fxy( ,2)= x y33 2++ −− − 3312 x y x 4
c. f()xy xy, =
f. fxy( ,3212)=−− + − +x^43 x y y^721 A T-shirt shop carries two competing shirts, one endorsed by Michael Jordan and
the other by Barry Bonds. The owner of the store can obtain both types at a cost
of $2 per shirt and estimates that if Jordan shirts are sold for x dollars apiece and
Bonds shirts for y dollars apiece, consumers will buy approximately
40 50−+x 40 yJordan shirts and 20 60+ x− 70 y Bonds
s in rder to generate th
(Answer: ݔ ൌ$2.70,ݕൌ$2.50ሻ
shirts each day. How
should the owner price the shirt o e largest possible profit?hagmYylk;GavyWtBIrRbePT. RbePTI1KWGav Michael Jordan mYyRbePTeTotKWGav Barry
Bonds. m©as;hagTijcUlGavyWtTaMgBIrRbePTenHedayéføedIm 2 duløakñúg1Gav². Kat;rMBwgfa
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