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Solve the given problem by using substitution. Find the maximum value of f(x,y,z) =8x2y2z2f ( x , y , z ) = 8 - x ^ { 2 } - y ^ { 2 } - z ^ { 2 } subject to z=3yz = 3 y .


A) fmax=8f _ { \max } = 8
B) fmax=9f _ { \max } = 9
C) fmax=3f _ { \max } = 3
D) fmax=10f _ { \max } = 10
E) fmax=7f _ { \max } = 7

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Locate the local maximum of the function. f(x,y) =x2y8x24y2f ( x , y ) = x ^ { 2 } y - 8 x ^ { 2 } - 4 y ^ { 2 }


A) (8,4,256) ( 8,4 , - 256 )
B) (0,0,0) ( 0,0,0 )
C) (8,8,256) ( - 8,8 , - 256 )
D) (8,4,0) ( - 8 , - 4,0 )
E) (8,8,256) ( 8,8 , - 256 )

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Compute the integral. 0408ex+y dx dy\int _ { 0 } ^ { 4 } \int _ { 0 } ^ { 8 } e ^ { x + y } \mathrm {~d} x \mathrm {~d} y


A) e8e4e ^ { 8 } e ^ { 4 }
B) (e81) (e41) \left( e ^ { 8 } - 1 \right) \left( e ^ { 4 } - 1 \right)
C) e12+12e ^ { 12 } + 12
D) e1212e ^ { 12 } - 12
E) e4(e51) \frac { e ^ { 4 } } { \left( e ^ { 5 } - 1 \right) }

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Use the given tabular representation of the function ff to compute f(2,4) f(4,2) f ( 2,4 ) - f ( 4,2 ) . x2468y2519718554919110046202012251981921623518\begin{array} { | l | l | l | l | l | l | } \hline & & \boldsymbol { x } & & & \\\hline & & \mathbf { 2 } & \mathbf { 4 } & \mathbf { 6 } & \mathbf { 8 } \\\hline \boldsymbol { y } & \mathbf { 2 } & - 5 & 197 & 185 & - 5 \\\hline & \mathbf { 4 } & - 9 & 191 & 100 & - 4 \\\hline & \mathbf { 6 } & - 20 & 201 & 225 & - 19 \\\hline & \mathbf { 8 } & - 19 & 216 & 235 & - 18 \\\hline\end{array}


A) -206
B) 188
C) 197
D) 206
E) -9

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What point on the surface z is closest to the origin z=x2+y2z = x ^ { 2 } + y - 2 Hint : Minimize the square of the distance from (x,y,z)( x , y , z ) to the origin. NOTE: Please enter your answer(s) in the form (x,y,z)( x , y , z ) . If there is more than one answer, separate them with commas.

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How many critical points does the function have f(x,y) =2xeyf ( x , y ) = 2 x e ^ { y }


A) three
B) two
C) four
D) one
E) none

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Find Rf(x,y) dx dy\iint _ { R } f ( x , y ) \mathrm { d } x \mathrm {~d} y , where f(x,y) =xy2f ( x , y ) = x y ^ { 2 } and R is the indicated domain. (Remember that you often have a choice as to the order of integration.)  Find  \iint _ { R } f ( x , y )  \mathrm { d } x \mathrm {~d} y  , where  f ( x , y )  = x y ^ { 2 }  and R is the indicated domain. (Remember that you often have a choice as to the order of integration.)         f ( y )  = \sqrt { 9 - y ^ { 2 } }    A) 32.4 B)  24.3 C)  16.2 D)  27 E)  259.2 f(y) =9y2f ( y ) = \sqrt { 9 - y ^ { 2 } }


A) 32.4
B) 24.3
C) 16.2
D) 27
E) 259.2

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Solve the given problem by using substitution. Minimize S=xy+25xz+5yzS = x y + 25 x z + 5 y z subject to xyz=1x y z = 1 with x>0x > 0 , y>0y > 0 , z>0z > 0 .


A) Smin=20S _ { \min } = 20
B) Smin=15S _ { \min } = 15
C) Smin=5S _ { \min } = 5
D) Smin=25S _ { \min } = 25
E) Smin=1S _ { \min } = 1

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Use Lagrange Multipliers to solve the problem. Find the maximum value of f(x,y) =3xyf ( x , y ) = 3 x y subject to x2+y2=8x ^ { 2 } + y ^ { 2 } = 8 .


A) fmax=24f _ { \max } = 24
B) fmax=12f _ { \max } = 12
C) fmax=17f _ { \max } = 17
D) fmax=7f _ { \max } = 7
E) fmax=32f _ { \max } = 32

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Compute the integral. 0104x25x(x+y) 12 dy dx\int _ { 0 } ^ { 10 } \int _ { 4 - x } ^ { 25 - x } ( x + y ) ^ { \frac { 1 } { 2 } } \mathrm {~d} y \mathrm {~d} x


A) 60
B) 15
C) -52
D) 780
E) 117

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Let H=fxx(a,b)fyy(a,b)f2xy(a,b)H = f _ { x x } ( a , b ) f _ { y y } ( a , b ) - f ^ { 2 } x y ( a , b ) What condition on H guarantees that f has a relative extremum at the point (a,b)( a , b )

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Your company manufactures two models of stereo speakers, the Ultra Mini and the Big Stack. Demand for each depends partly on the price of the other. If one is expensive then more people will buy the other. If p1 is the price per pair of the Ultra Mini and p2 is the price of the Big Stack, demand for the Ultra Mini is given by q1(p1,p2) =50,000100p1+10p2q _ { 1 } \left( p _ { 1 } , p _ { 2 } \right) = 50,000 - 100 p _ { 1 } + 10 p _ { 2 } Where q1 represents the number of pairs of Ultra Minis that will be sold in a year. The demand for the Big Stack is given by q2(p1,p2) =150,000+10p1100p2q _ { 2 } \left( p _ { 1 } , p _ { 2 } \right) = 150,000 + 10 p _ { 1 } - 100 p _ { 2 } Find the prices for the Ultra Mini and the Big Stack that will maximize your total revenue. Round your answer to the nearest dollar.


A) $798 for Ultra Mini and $275 for Big Stack
B) $428 for Ultra Mini and $783 for Big Stack
C) $275 for Ultra Mini and $798 for Big Stack
D) $328 for Ultra Mini and $783 for Big Stack
E) $783 for Ultra Mini and $328 for Big Stack

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Evaluate f(a,2) f ( a , 2 ) for f(x,y) =x2yxy+5f ( x , y ) = x ^ { 2 } - y - x y + 5


A) a22aa ^ { 2 } - 2 a
B) a22a+3a ^ { 2 } - 2 a + 3
C) a2+2a2a ^ { 2 } + 2 a - 2
D) a22a2a ^ { 2 } - 2 a - 2
E) a22a+5a ^ { 2 } - 2 a + 5

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Locate the saddle point of the function. f(x,y) =x26x+yeyf ( x , y ) = x ^ { 2 } - 6 x + y - e ^ { y }


A) (6,1,10) ( 6,1 , - 10 )
B) (6,1,1) ( 6,1 , - 1 )
C) (3,0,10) ( 3,0 , - 10 )
D) (6,0,10) ( 6,0 , - 10 )
E) (3,1,10) ( 3,1 , - 10 )

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For the function p(x,y) =x0.2y+0.44xyp ( x , y ) = x - 0.2 y + 0.44 x y Find p(40,20) p ( 40,20 ) .


A) 364
B) 396
C) 388
D) 376
E) 752

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Locate the local maximum of the function. f(x,y) =e(x6+y2) f ( x , y ) = e ^ { - \left( x ^ { 6 } + y ^ { 2 } \right) }


A) (0,0,1) ( 0,0,1 )
B) (1,0,1e) \left( 1,0 , \frac { 1 } { e } \right)
C) (0,0,0) ( 0,0,0 )
D) (1,0,e) ( 1,0 , e )
E) (1,0,1e2) \left( 1,0 , \frac { 1 } { e ^ { 2 } } \right)

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Compute the integral. 09x2x2x dy dx\int _ { 0 } ^ { 9 } \int _ { - x ^ { 2 } } ^ { x ^ { 2 } } x \mathrm {~d} y \mathrm {~d} x


A) 3,280.5
B) 9
C) 6,561
D) -40.5
E) 0

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If positive electric charges of Q and q coulombs are situated at positions (a,b,c)( a , b , c ) and (x,y,z)( x , y , z ) , respectively, then the force of repulsion they experience is given by F=KQq(xa)2+(yb)2+(zc)2F = K \frac { Q q } { ( x - a ) ^ { 2 } + ( y - b ) ^ { 2 } + ( z - c ) ^ { 2 } } Where K9×109K \approx 9 \times 10 ^ { 9 } , F is given in newtons, and all positions are measured in meters. Assume that a charge of 4 coulombs is situated at the origin and that a second charge of 14 coulombs is situated (1,4,3)( 1,4,3 ) and moving in the y direction at 1.4 meters per second. How fast is the electrostatic force it experiences decreasing NOTE: Please enter your answer without the units. Round the answer to the nearest trillion.

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Write the integral with the order of integration reversed (changing the limits of integration as necessary) . 1101+yf(x,y) dx dy\int _ { - 1 } ^ { 1 } \int _ { 0 } ^ { \sqrt { 1 + y } } f ( x , y ) \mathrm { d } x \mathrm {~d} y


A) 02x11f(x,y) dy dx\int _ { 0 } ^ { \sqrt { 2 } } \int _ { \sqrt { x } - 1 } ^ { 1 } f ( x , y ) \mathrm { d } y \mathrm {~d} x
B) 02x211f(x,y) dy dx\int _ { 0 } ^ { \sqrt { 2 } } \int _ { x ^ { 2 } - 1 } ^ { 1 } f ( x , y ) \mathrm { d } y \mathrm {~d} x
C) 011x21f(x,y) dy dx\int _ { 0 } ^ { 1 } \int _ { 1 } ^ { x ^ { 2 } - 1 } f ( x , y ) \mathrm { d } y \mathrm {~d} x
D) 10x211f(x,y) dy dx\int _ { - 1 } ^ { 0 } \int _ { x ^ { 2 } - 1 } ^ { 1 } f ( x , y ) \mathrm { d } y \mathrm {~d} x
E) 02x11f(x,y) dy dx\int _ { 0 } ^ { \sqrt { 2 } } \int _ { \sqrt { x - 1 } } ^ { 1 } f ( x , y ) \mathrm { d } y \mathrm {~d} x

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Use Lagrange Multipliers to solve the given problem. Find the maximum value of f(x,y) =xyf ( x , y ) = x y subject to 2x+y=602 x + y = 60 .


A) fmax=10f _ { \max } = 10
B) fmax=450f _ { \max } = 450
C) fmax=30f _ { \max } = 30
D) fmax=2f _ { \max } = 2
E) fmax=225f _ { \max } = 225

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