1 / 28

Quiz review

8.4 ELLIPSES. Definition / featuresStandard form / features graphDeriving formulaFinding equation given featuresRewriting in standard form. Definition of ellipse. An ellipse is the set of points in a plane such that the sum of the distances from two fixed points (called foci) is constantSee

asis
Télécharger la présentation

Quiz review

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. Quiz review Circle equation: (x h)2 + ( y k)2 = r2 Recall relevant vocab: diameter, tangent For parabolas, either: y = a(x h)2 + k OR: x = a(y k)2 + h For parabolas, a = 1/4p, where p is the distance from the VERTEX to the focus and to the directrix FOR BOTH TYPES OF CONICS: - Given equation, find the features - Given some features, find the equation - Rewrite an equation in standard form (use completing the square) ALSO - know the distance and midpoint formula, review slope formula - Be able to show that segments are congruent, parallel, or perpendicular, or that one segment bisects another!

    2. 8.4 ELLIPSES Definition / features Standard form / features + graph Deriving formula Finding equation given features Rewriting in standard form

    3. Definition of ellipse An ellipse is the set of points in a plane such that the sum of the distances from two fixed points (called foci) is constant See graph on board Other features of ellipse: - center - major axis + endpoints - minor axis + endpoints

    4. Standard form of ellipse The standard form of an ellipse is: (x h)2 + (y k)2 = 1 a2 b2 Where (h,k) are the coords of the center a is the length of the major axis b is the length of the minor axis NOTE that a and b can switch places depending on the orientation of the ellipse! That is, if the ellipse is horizontally oriented (see board) then a2 will be underneath the x-term if the ellipse is vertically oriented, a2 will be underneath the y-term

    5. a, b, c The other feature of the ellipse, the foci, can be found using a and b We call c the distance from the center to a focus The relationship between a,b and c is: c2 = a2 b2 So if we know a and b we can find the coordinates of the foci

    6. Example 4-3a

More Related