PRE-CALCULUS 11
IdentifyandDescribethePicture
IdentifyandDescribethePicture
IdentifyandDescribethePicture
IdentifyandDescribethePicture
What do you notice
about the
pictures?
IdentifyandDescribethePicture
LEARNINGOBJECTIVES
01 define an ellipse
03
graph an ellipse in a
rectangular coordinate
system given an
equation with center at
(0,0)
02
determine the standard
form of equation of an
ellipse with center at
(0,0)
ELLIPSE
LESSON 4
SimpleIllustrationofEllipse
Definition of Ellipse
An ellipse is a set of points
such that the sum of the
distances from two fixed
points is constant.
The fixed points are the foci,
and the constant sum is the
length of major axis.
ELLIPSE
F F
P(x,y)
𝑑1
𝑑2
𝑑1 + 𝑑2 = 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡
The ellipse
intersects the
major axis called
vertices, denoted
as V1 and V2.
The length of the
segment V1V2 is
equal 2a.
PropertiesofEllipse
𝑉1 𝑉2
2𝑎
𝑎
The midpoint of
the segment
V1V2 is called the
center of the
ellipse, denoted
by C.
PropertiesofEllipse
𝑉1 𝑉2
𝐶
The line segment
through the center
perpendicular to
the major axis is
the minor axis,
denoted as B1B2
which are the
covertices.
The length of the
line segment is
equal to 2b.
PropertiesofEllipse
𝑉1 𝑉2
𝐶
𝐵1
𝐵2
2𝑏
𝑏
The length of the
line segment
F1F2 is 2c.
The line segment
through F1 and
F2 are called the
latera recta and
each has a length
of
2𝑏2
𝑎
.
PropertiesofEllipse
𝑉1 𝑉2
𝐶
𝐵1
𝐵2
𝐹1
𝐹2
2𝑐
𝑐
The length of the
line segment
F1F2 is 2c.
The line segment
through F1 and
F2 are called the
latera recta and
each has a length
of
2𝑏2
𝑎
.
PropertiesofEllipse
𝑉1 𝑉2
𝐶
𝐵1
𝐵2
𝐹1
𝐹2
2𝑏2
𝑎
𝑏2
𝑎
𝐸1
𝐸2
𝐸3
𝐸4
In ellipse,
a>b
a>c
If a=b, then the
ellipse is circle.
𝑐2 = 𝑎2 − 𝑏2
PropertiesofEllipse
𝑉1 𝑉2
𝐶
𝐵1
𝐵2
𝐹1
𝐹2
𝐸1
𝐸2
𝐸3
𝐸4
Definition of Ellipse
An ellipse is a set of points
such that the sum of the
distances from two fixed
points is constant.
The fixed points are the foci,
and the constant sum is the
length of major axis.
ELLIPSE
F F
P(x,y)
𝑑1
𝑑2
𝑑1 + 𝑑2 = 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡
2𝑎
GENERALFORMANDFORMULAS
𝑨𝒙𝟐 + 𝑪𝒚𝟐 + 𝑫𝒙 + 𝑬𝒚 + 𝑭 = 𝟎
GeneralformofanEllipseequation
whereinBismissing,andthe
numericalcoefficientsof𝑥2
and𝑦2
havethesamesigns.
CENTERATORIGIN(0,0)
𝒙𝟐
𝒂𝟐
+
𝒚𝟐
𝒃𝟐
= 𝟏
𝒙𝟐
𝒃𝟐
+
𝒚𝟐
𝒂𝟐
= 𝟏
LET’SPRACTICE
𝒙𝟐
36
+
𝒚𝟐
18
= 𝟏
𝒙𝟐
4
+
𝒚𝟐
16
= 𝟏
WHATIS𝑎𝟐? 𝑏𝟐?
EXAMPLE1
Sketch the graph and determine the coordinates of the foci, vertices, and covertices
𝒙𝟐
𝟐0
+
𝒚𝟐
36
= 𝟏
EXAMPLE 2
Sketch the graph and determine the coordinates of the foci, vertices, and covertices
𝟐𝟓𝒙𝟐
+ 𝟒𝒚𝟐
= 𝟏𝟎𝟎
EXAMPLE 3
Find and graph the equation of the ellipse a which satisfies the following conditions:
Foci at (±2,0); one vertex at (4,0)
EXAMPLE4
Sketch the graph and determine the coordinates of the foci, vertices, and covertices
𝒙𝟐
9
+
𝒚𝟐
16
= 𝟏
ACTIVITY5
A. Sketch the graph and determine the coordinates of the foci,
vertices, and covertices of this ellipse.
𝑥2
16
+
𝑦2
25
= 1
B. Determine the standard form of equation of an ellipse given:
Vertices (0, ±5); minor axis of length 6
ASSESSMENT
𝒙 − 𝒉 𝟐
𝒂𝟐 +
𝒚 − 𝒌 𝟐
𝒃𝟐 = 𝟏
𝒙 − 𝒉 𝟐
𝒃𝟐 +
𝒚 − 𝒌 𝟐
𝒂𝟐 = 𝟏
VERTEXAT(h,k)
EXAMPLE1
Give the coordinates of the foci, vertices, and covertices
(𝒙 + 3)𝟐
𝟐4
+
(𝒚 − 5)𝟐
4𝟗
= 𝟏
EXAMPLE1
Give the coordinates of the foci, vertices, and covertices of the given general form of
ellipse.
𝟗𝒙𝟐 + 𝟏𝟔𝒚𝟐 − 𝟏𝟐𝟔𝒙 + 𝟔𝟒𝒚 = 𝟕𝟏
EXAMPLE1
The foci of an ellipse are (−3,−6) and (−3, 2). For any point on the ellipse, the sum of
its distances from the foci is 14. Find the standard equation of the ellipse and give
the coordinates of the center, vertices and covertices.
ASSIGNMENT

lesson4.-ellipse f.pptx

Editor's Notes

  • #21 Always remember, the major axis contains the center, the foci, and the vertices.
  • #22 Balik sa definition. The sum of the focal distances of any point on the ellipse is constant and that is equal to 2a. (PF1 + PF2 = 2a)
  • #30 Optional. Pwedeng isang at origin or isang hk
  • #31 Optional. Pwedeng isang at origin or isang hk