Finite Math |
Test #1
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Oct. 10, 2000
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F Track |
R. Hammack
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Name: ________________________ |
Score: _________
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(1) Perform the indicated matrix operation, or explain why it cannot be done.
(a) | [ |
5
|
1
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][ |
1
|
4
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] |
=
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|
2
|
3
|
2
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0
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(b) | [ |
0
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-1
|
3
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] |
+
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[ |
0
|
1
|
2
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] | = | |
4
|
7
|
1
|
-5
|
2
|
5
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(2) Sketch the solutions of the following system of inequalities.
2x1
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+
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x2
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≤
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8 |
x1
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+
|
x2
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≤
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5 |
x1
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+
|
2x2
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≤
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8 |
x1
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≥
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0 |
x2
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≥
|
0 |
(3)
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Maximize subject to ...
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P = 10x1 + x2
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You may use any method. (However, notice that you sketched the feasible region in the previous problem. Feel free to use that information here.)
(4) Use Gauss-Jordan elimination to solve the following system of equations:
2x1
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+
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4x2
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+
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2x4
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=
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6 | ||
x1
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+
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2x2
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+
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x3
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+
|
2x4
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=
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4 |
(5) Use the simplex method to solve the following problem.
A small publishing company is considering whether to publish 3 books. Let's call them book A, book B and book C. Two machines are needed to print the books, a printer and a binder. First a book is printed on the printer, then it is fed into the binder. Each copy of book A takes 6 minutes on the printer, then 4 minutes on the binder. Each copy of book B takes 4 minutes on the printer, then 2 minutes on the binder. Each copy of book C takes 2 minutes on the printer, then 1 minute on the binder. The printer is available for 1000 minutes per week, and the binder is available for 800 minutes per week. Each copy of book A will bring a profit of $2, each copy of book B will bring a profit of $1, and each copy of book C will bring a profit of $3. How many copies of each book shuld be made to realize a maximum profit?