6.2 graphs of polynomials
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6.2 Graphs of Polynomials. The Degree of Polynomials. The degree of a polynomial is the value of the largest exponent. y = 5x 4 + 3x 2 – 7 Degree = 4 y = -7x 5 + 2x 9 + 3x 2 – 5x 4 + 2 Degree = 9. The Leading Coefficient of a Polynomial. - PowerPoint PPT PresentationTRANSCRIPT
The Degree of Polynomials
The degree of a polynomial is the value of the largest exponent.
y = 5x4 + 3x2 – 7
Degree = 4
y = -7x5 + 2x9 + 3x2 – 5x4 + 2
Degree = 9
The Leading Coefficient of a Polynomial
The leading coefficient of a polynomial is the value of coefficient of the term with the largest exponent.
y = 5x4 + 3x2 – 7
Leading Coefficient = 5
y = -7x5 + 2x9 + 3x2 – 5x4 + 2
Leading Coefficient = 2
Graphs of Polynomials with Odd Degreesy = x y = x3 y = x5
y = -x5y = -x y = -x3
Odd degree polynomials are like lines. They start low and end high
Unless they have a negative leading coefficient. Then they start high and end low.
Graphs of Polynomials with Even Degreesy = x6
y = x2 y = x4
y = -x2 y = -x4 y = -x6
Even degree polynomials are like parabolas. They start high and end high
Unless they have a negative leading coefficient. Then they start low and end low.
Roots of Polynomials
What are the roots of y = -5 (x - 5)(x - 2)(x + 4)(x + 7)?
What is its degree?
What about the leading coefficient?
Roots of Polynomials
What are the roots of y = 3 (x - 5)(x - 2)2?What is its degree?
What about the leading coefficient?
Roots of Polynomials
What are the roots of y = (x - 5)2(x - 2)2?
What is its degree?
What about the leading coefficient?
Roots of Polynomials
What are the roots of y = (x + 3)(x - 5)2(x - 2)2?
What is its degree?
What about the leading coefficient?
Roots of PolynomialsWhat are the roots of y = -(x + 3)3(x - 5)?
What is its degree?
What about the leading coefficient?
Roots of PolynomialsWhat are the roots of y = -(x + 3)3(x - 5)2(x + 7)3?What is its degree?
What about the leading coefficient?
Graphs of Polynomials
To graph a polynomial in factored form:
1.) Determine the degree
2.) Check the sign of the leading coefficient.
3.) Mark on your graph where the curve begins and ends (the end behavior)
4.) Plot the position of the roots.
5.) Connect the dots.
When connecting the dots, don’t forget to check the degree of each root.
Single Roots = Straight through the x-axis (like a line).
Double Roots = Bounce off the x-axis (like a parabola).
Triple Roots = The line bends as it passes through the x-axis (like a cubic).