The vertex form of a parabola is given
The vertex form of a parabola is given as: f(x) = a (x – h)2 + k a indicates a reflection across the x axis if its negative and/or a vertical stretch or compression h indicates a horizontal Translation (shift) k indicates a vertical translation (shift)
Vertex is: (h, k) so (3, 4) Axis of symmetry is: x = h so x = 3 Minimum or maximum value is k Here, the function has a minimum value of 4
Name the following: Vertex: Axis of symmetry: Minimum or maximum
Find the equation of the parabola We know: Vertex = (0, -2) (1, 1) f(x) = a(x + 0)2 – 2 f(x) = ax 2 - 2 Find a using a point other than the vertex: f(x)= ax 2 - 2 1= a(1)2 - 2 1=a– 2 3=a so vertex form is: f(x) = 3 x 2 - 2
Find vertex form of the parabola: (-2, 5) (0, 3)
Using the calculator, find the zero’s of the function – where the graph crosses the x axis 1. 2. 3. 4. Graph the function Press 2 nd – calc Down arrow to #2 zero Enter 5. Use right arrow to move blinking curser before the first zero -- enter 6. Use right arrow to move curser after the zero -- enter 7. Hit enter again to get the value of the zero The two zero’s are at x = ____ and x = ____
How many zero’s here? What does the equation of this graph seem to be?
Do the following in the green workbook: p. 332 a-e, 2 a and 2 b p. 333 p. 335 #1 -4 p. 336 #7 -10 p. 337 #2, 3 4
- Slides: 8