1 / 20

Conics: a crash course

Conics: a crash course. MathScience Innovation Center Betsey Davis. Why “conics”?. The 4 basic shapes are formed by slicing a right circular cone. What is a right circular cone?. A cone, with a circular base, whose axis is perpendicular to that base. Not right circular cone:.

avedis
Download Presentation

Conics: a crash course

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Conics: a crash course MathScience Innovation Center Betsey Davis

  2. Why “conics”? • The 4 basic shapes are formed by slicing a right circular cone What is a right circular cone? • A cone, with a circular base, whose axis is perpendicular to that base. Conics B. Davis MathScience Innovation Center

  3. Not right circular cone: Conics B. Davis MathScience Innovation Center

  4. What are the 4 basic conics? • Parabola • Circle • Ellipse • Hyperbola Conics B. Davis MathScience Innovation Center

  5. What is the relationship between the cone and the 4 shapes? • It’s how you slice ! Conics B. Davis MathScience Innovation Center

  6. Take notes on first site! You will be responsible for knowing some real-world applications of each of the conics. Slicing a cone Let’s visit 1http://id.mind.net/~zona/mmts/miscellaneousMath/conicSections/conicSections.htm 2http://ccins.camosun.bc.ca/~jbritton/jbconics.htm 3http://www.keypress.com/sketchpad/java_gsp/conics.html 4http://www.exploremath.com/activities/activity_list.cfm?categoryID=1 Conics B. Davis MathScience Innovation Center

  7. General Equation: • Ax^2 + Bxy + Cy^2 + Dx + Ey + F = 0 • For us, • B = 0 always • (this rotates the conic between 0 and 90 degrees) Conics B. Davis MathScience Innovation Center

  8. General Equation: • Ax^2 + By^2 + Cx + Dy + E = 0 • What is the value of A or B if it is a parabola? • B=0 or A =0 but not both Conics B. Davis MathScience Innovation Center

  9. General Equation: • Ax^2 + By^2 + Cx + Dy + E = 0 • If circle • B=A Conics B. Davis MathScience Innovation Center

  10. General Equation: • Ax^2 + By^2 + Cx + Dy + E = 0 • If ellipse • B is not equal to A, but they have the same sign Conics B. Davis MathScience Innovation Center

  11. General Equation: • Ax^2 + By^2 + Cx + Dy + E = 0 • If hyperbola • B and A have opposite signs Conics B. Davis MathScience Innovation Center

  12. Parabola • Circle • Ellipse • Hyperbola General Equation: • 3x^2 + 3y^2 + 2x + y + 8 = 0 • 3x^2 - 3y^2 + 2x + y + 8 = 0 • 3x^2 + 9y^2 + 2x + y + 8 = 0 • 3x^2 + 2x + y + 8 = 0 Conics B. Davis MathScience Innovation Center

  13. Parabola Reminders • Parabolas opening up and down are the only conics that are functions • Y = (x-3)^2 +4 • Vertex? • Axis of symmetry? • Opening which way? (3,4) X = 3 up Conics B. Davis MathScience Innovation Center

  14. Parabola Reminders • Y^2 –4Y + 3 –x = 0 • Vertex? • Axis of symmetry? • Opening which way? (-1,2) Y=2 right Conics B. Davis MathScience Innovation Center

  15. Circles • Ax^2 + Ay^2 +Cx + Dy + E= 0 • (x-h)^2 + (y-K)^2 = r^2 • Where (h,k) is the center and r is the radius • X^2 + y^2 = 36 • Centered at origin • Radius is 6 Conics B. Davis MathScience Innovation Center

  16. Circles • Ax^2 + Ay^2 +Cx + Dy + E= 0 • (x-h)^2 + (y-K)^2 = r^2 • Where (h,k) is the center and r is the radius • (X-1)^2 +( y-3)^2 = 49 • Center at (1,3) • Radius is 7 Conics B. Davis MathScience Innovation Center

  17. Ellipses • Ax^2 + By^2 +Cx + Dy + E= 0 • (x-h)^2 + (y-K)^2 = 1 a^2 b^2 • Where (h,k) is the center and a is the long radius and b is the short radius • (X)^2 +( y)^2 = 1 • 25 4 • Center at (0,0) • Major axis 10, minor 4 Conics B. Davis MathScience Innovation Center

  18. Ellipses • Ax^2 + By^2 +Cx + Dy + E= 0 • (x-h)^2 + (y-K)^2 = 1 a^2 b^2 • Where (h,k) is the center and a is the long radius and b is the short radius • (X-1)^2 +( y+3)^2 = 1 • 16 100 • Center at (1,-3) • Major axis 20, minor 8 Conics B. Davis MathScience Innovation Center

  19. Hyperbolas • Ax^2 - By^2 +Cx + Dy + E= 0 • (x-h)^2 - (y-K)^2 = 1 a^2 b^2 • Where (h,k) is the center and 2a is the transverse axis • (X-1)^2 -( y+3)^2 = 1 • 16 100 • Center at (1,-3) • Transverse axis length is 8 Conics B. Davis MathScience Innovation Center

  20. Hyperbolas • Ax^2 - By^2 +Cx + Dy + E= 0 • (x-h)^2 - (y-K)^2 = 1 a^2 b^2 • Where (h,k) is the center and 2a is the transverse axis • (y)^2 - ( x)^2 = 1 • 16 100 • Center at (0,0) • Transverse axis length is 8 Conics B. Davis MathScience Innovation Center

More Related