Sketching Parabolas

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Sketching Parabolas

• Algebra 1
• Tuesday, October 29, 2013

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Who came up with the Quadratic Formula?
900 B.C. First recorded symbol for Zero
1947 A.D Jackie Robinson
2400 B.C Papyrus in Egypt
1 B.C.
3000 B.C Sumerians divide day into 24 hrs
1800 B.C. Babylonians have multiplication table
44 B.C Caeser assassinated
1633 A.D Galileo condemned to death
http//www.au.af.mil/au/awc/awcgate/timeline/time0
002.htm
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(No Transcript)
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Who came up with the Quadratic Formula?
900 B.C. First recorded symbol for Zero
1947 A.D Jackie Robinson
2400 B.C Papyrus in Egypt
1 B.C.
3000 B.C Sumerians divide day into 24 hrs
1800 B.C. Babylonians have multiplication table
44 B.C Julius Caeser assassinated
1633 A.D Galileo condemned to death
http//www.au.af.mil/au/awc/awcgate/timeline/time0
002.htm
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Discriminant- the value inside the radical (
) when you do the quadratic formula.
This value can be positive, zero, or negative.
Roots of a Polynomial- the answer(s) for x.
Where the graph of the parabola intersects the
x-axis. There can be two roots, one root, or No
roots.
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Two Roots


Positive
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One Root
Zero
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No Roots
Negative
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Discriminant- the value inside the radical (
) when you do the quadratic formula.
This value can be positive, zero, or negative.
Roots of a Polynomial- the answer(s) for x.
Where the graph of the parabola intersects the
x-axis. There can be two roots, one root, or No
roots.

• Parabola- the type of curve you get when you
  neatly graph a quadratic equation.
• Positive, or upward, parabolas have a minimum
  point.

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When the a in, ax2, is Positive
Upward
Happy
Minimum
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Discriminant- the value inside the radical (
) when you do the quadratic formula.
This value can be positive, zero, or negative.
Roots of a Polynomial- the answer(s) for x.
Where the graph of the parabola intersects the
x-axis. There can be two roots, one root, or No
roots.

• Parabola- the type of curve you get when you
  neatly graph a quadratic equation.
• Positive, or upward, parabolas have a minimum
  point.
• Negative, or downward, parabolas have a maximum
  point.

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When the a in, ax2, is Negative
Maximum
Downward
Sad
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Discriminant- the value inside the radical (
) when you do the quadratic formula.
This value can be positive, zero, or negative.
Roots of a Polynomial- the answer(s) for x.
Where the graph of the parabola intersects the
x-axis. There can be two roots, one root, or No
roots.

• Parabola- the type of curve you get when you
  neatly graph a quadratic equation.
• Positive, or upward, parabolas have a minimum
  point.
• Negative, or downward, parabolas have a maximum
  point.
• Parabolas are symmetrical along their vertical
  line of symmetry which is always halfway
  between points of equal height.

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Symmetry
- - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - -
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Discriminant (b2-4ac) Number of Roots (Number of answers) Sketch of Sample Graph



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Deriving the Quadratic Formula