2. polynomial and rational functions - 2.01 CHAPTER 2 POLYNOMIAL AND RATIONAL FUNCTIONS SECTION 2.1 QUADRATIC FUNCTIONS(AND PARABOLAS PART A BASICS If a

2. polynomial and rational functions - 2.01 CHAPTER 2...

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2.01 CHAPTER 2: POLYNOMIAL AND RATIONAL FUNCTIONS SECTION 2.1: QUADRATIC FUNCTIONS (AND PARABOLAS) PART A: BASICSIf a, b, and care real numbers, then the graph offx( )=y=ax2+bx+cis a parabola, provided a0If a>0, it opens upwardIf a<0, it opens downward . . .
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2.02 PART B: FINDING THE VERTEX AND THE AXIS OF SYMMETRY (METHOD 1)The vertex of the parabola [with equation] y=ax2+bx+cis h,k(), where:x-coordinate=h=b2a, andy-coordinate=k=fh( ).The axis of symmetry, which is the vertical line containing the vertex,has equation x=h(Does the formula for hlook familiar? We will discuss this later.)ExampleFind the vertex of the parabola y=x26x+5. What is its axis of symmetry? . . .
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2.03 PART C: FINDING MORE POINTS“Same” Example: y=x26x+5, or fx( )=x26x+Find the y-intercept.Plug in 0 for x. Solve for yIn other words, find f0( )The y-intercept is 5(If the parabola is given by y=ax2+bx+c, then c, the constant term, is they-intercept. Remember that bwas the y-intercept for the line given byy=mx+b.)Find the x-intercept(s), if any. 5 . . . . 5 . - .
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