chapter 7.1: matrices and systems of linear...
TRANSCRIPT
CA Ch 7.1.notebook
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For all real numbers x, the minimum value of 1 + 2cos(4x) is
A) 0
B) 1
C) 1
D) 2
E) 4
ACT Question:
Chapter 7.1: Matrices and Systems of Linear EquationsA matrix is a rectangular array of numbers written within brackets.
Rows
Columns
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Determine the order of each matrix given.
A coefficient matrix is one whose elements are the coefficients of a system of linear equations. An augmented matrix is used to solve systems of linear equations.
Items to note:Each row is an equationThe vertical line is the equal signEach column represents a variableAny variable that is not in the equation is a 0 in the matrix
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Write each system as an augmented matrix.
Row Operations on a Matrix
Interchange Rows
Multiply Rows by a constant
Add/Subtract Rows
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For each matrix, Perform the given operation.
RowEchelon Form:A matrix is in RowEchelon Form if...1. And rows consisting entirely of 0's are at the bottom of the matrix.2. For each row that does not consist of 0's, the first non zero entry is 1.
3. For two successive nonzero rows, the leading 1 in the higher row is farther left then the lower row.
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Reduced RowEchelon Form:
4. Every column containing a leading 1 has zeros in every position above and below the leading 1
Determine if each matrix is in REF or RREF.
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Gaussian Elimination with BackSubstitution
Step 1: Write the system as an augmented matrixStep 2: Use row operations to rewrite the augmented matrix in rowechelon form
Step 3: Write the system of linear equations that corresponds to the matrix in rowechelon form found in Step 2
Step 4: Use the system of linear equations found in Step 3 together with backsubstitution to find the solution of the
Solve using Gaussian Elimination(REF)
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Solve using Gaussian Elimination(REF)
GaussJordan Elimination(RREF)Step 1: Write the system of linear equations as an augmented matrix.Step 2: Uses row operations to rewrite the augmented matrix in reduced rowechelon form.Step 3: Write the system given by Step 2. The result should be the solution
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Solve using GaussJordan Elimination(RREF)
Solve using GaussJordan Elimination(RREF)
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Independent
Inconsistent
Dependent
One unique solution
No Solution
Infinitely many solutions
Solve the system:
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Solve the system:
Solve the system of linear equations
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Applications: Suppose you are going to eat only Subway 6inch sandwiches for a week(7 days) for both lunch and dinner(total 14 meals). If you goal is to eat 388 grams of protein and 4900 calories in those 14 sandwiches, how many of each sandwich should you eat that week?
Sandwich Cal Fat Carbs ProteinVeggie 350 18 17 36Roasted Chicken 430 19 46 20
Ham 290 5 45 19
The amount of money awarded in medical malpractice suits is rising. This can be modeled with a quadratic function , where a>0 and t>0
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Suggested Problems: Ch 7.1 pg.647 #'s 1,9,11,19,23,27,33,39,43,49,53,
63,65,71,75,85,87,95,105,116