conic section ppt
TRANSCRIPT
SMN3023
ADVANCED CALCULUS
GROUP C
NAME MATRIX NUMBER
CHAN LEE LING D20092036897
ASMIDA BINTI CHE ME D20091034995
NOORUL ASMA BINTI ABDUL SAMAT D20092036907
SITI NAILAH SAKINAH BINTI MOHD SALEH D20091035018
WHAT DOES IT MEAN BY CONIC SECTION?
A conic section is the intersection of a plane and a cone.
Circle Ellipse(h) Parabola(h) Hyperbola(h)
Ellipse(v) Parabola(v) Hyperbola(v)
By changing the angle and location of intersection, we can
produce a circle, ellipse, parabola or hyperbola; or in the special
case when the plane touches the vertex: a point, line or 2
intersecting lines
Point Line Double Line
2 2 0Ax Bxy Cy Dx Ey F
The type of section can be found from the sign of:
then the curve is a...
< 0 ellipse, circle, point or no curve.
= 0 parabola, 2 parallel lines, 1 line or no curve
> 0 hyperbola or 2 intersecting lines.
2If 4 is.......b ac
General Equation for a Conic Section
TYPE OF CONIC SECTION
Circle Ellipse Hyperbola Parabola
FORMING OF CONIC SECTIONS
The conics get their name from the fact that
they can be formed by passing a plane
through a double-napped cone
CONIC SECTIONS : CIRCLE
DEFINITION OF CIRCLE
A circle is all points equidistant (the distance is called the radius)
from one point (which is called the center of the circle).
A circle can be formed by slicing a right circular cone with a plane traveling parallel to the base of
the cone.
RELATED TERMS IN CIRCLE
Arc: a curved line that is part of the circumference of a circle
Chord: a line segment within a circle that touches 2 points on the circle.
Circumference: the distance around the circle.
Diameter: the longest distance from one end of a circle to the other.
Origin: the center of the circle Pi: A number, 3.141592…, equal to
(the circumference) / (the diameter) of any circle.
Radius: distance from center of circle to any point on it.
Sector: is like a slice of pie (a circle wedge).
Tangent of circle: a line perpendicular to the radius that touches ONLY one point on the circle.
HOW TO GRAPH A CIRCLE
Centre at the originCentre away from the origin
CENTRE AT THE ORIGIN Realize that the circle is centered at the
origin and place this point there. Calculate the radius by solving for r Plot the radius points on the coordinate
plane. Connect the dots to graph the circle using a
smooth, round curve.
CENTRE AWAY FROM THE ORIGIN
Locate the center of the circle from the equation (h, v).
Calculate the radius by solving for r. Plot the radius points on the coordinate
plane. Connect the dots to the graph of the circle
with a round, smooth curve
EXAMPLE
Show that the expression
represents the equation of a circle. Find its centre and radius.
SOLUTION Using completing the square
taking the free constants to the right-hand side
By comparing this with the standard form we conclude this represents the equation of a circle with centre at coordinate position (1, -3) and radius 2
The circle, as a wheel, is one of the greatest
inventions of all time and the basis of much of
our transportation system. Circular gears are
important elements in many of the machines we
use every day, from CD players to electric saws.
CIRCLES IN REAL LIFE APPLICATION
CIRCLES IN REAL LIFE APPLICATION
The distance around a circle is called the
circumference. The formula for finding the
circumference of a circle is "circumference of a
circle equals pi times the diameter of the circle":
CONIC SECTION : ELLIPSE
INTRODUCTION
An ellipse is a plane
curve that results from the
intersection of a cone by
a plane in a way that
produces a closed curve.
THE PARTS OF THE ELLIPSE
An ellipse has two lengths (major
and minor axes)
Vertices of an ellipse are the
endpoints of the major axis
Foci of the ellipse always lie on the
major axis
THE EQUATION OF THE ELLIPSE
The point F1 and F2 are called
the foci (plural of focus) of the
ellipse.
The point P is a typical point
on the ellipse.
If we denote this constant by
2a, a > 0, then |PF1| + |PF2| =
2a for any point P on the
ellipse.
THE EQUATION OF THE ELLIPSE d1 is the distance between (x,y)
and (-c,0) and d2 is the distance
between (x,y) and (c,0).
After substituting, we have our
desired equation:
HORIZONTAL ELLIPSE
Center: (0, 0)
Vertices: (a, 0) (-a, 0)
Foci: (c, 0) (-c, 0)
Major Axis: 2a
Minor Axis: 2b
Distance between foci:
2c
VERTICAL ELLIPSE
Center: (0, 0)
Vertices: (a, 0) (-a, 0)
Foci: (c, 0) (-c, 0)
Major Axis: 2a
Minor Axis: 2b
Distance between foci:
2c
TRANSLATION OF ELLIPSE
Center: (h, k)
Vertices: (a+h, k) (-a+h, k)
Foci: (c+h, k) (-c+h, k)
Major Axis: 2a
Minor Axis: 2b
Distance between foci:
2c
GEOMETRY OF ELLIPSE
The focal constant is equal to the
major axis.
Since the point (a, 0) is on the ellipse,
the sum of the distances from (a, 0) to
the foci (c, 0) and (-c, 0) equals the
focal constant. This distance is :
GEOMETRY OF ELLIPSE
Since the distance from (0, b)
to each focus is equal, the
distance from (0, b) to each
focus must equal a.
This creates a right triangle
with legs of length b and c, and
hypotenuse of length a, giving
the relation
APPLICATION OF ELLIPSE: SOLAR SYSTEM
The orbits of the planets are
ellipses, with the Sun at one focus of
the ellipse.
The orbits of the moon and of
artificial satellites of the earth are
also elliptical as are the paths of
comets in permanent orbit around
the sun
APPLICATION OF ELLIPSE: ELLIPTICAL GEAR
An ellipse is defined by a set of
points in a plane
This enables elliptical gears cut
about their foci to run at a constant
center distance.
Using precision elliptical bilobe
gears, flowmeters can have good
linearity over a wide range of flow
rates and viscosities.
CONIC SECTIONS : HYPERBOLA
DEFINITION•A hyperbola is the set of all points (x, y) such that the difference of the distances between (x, y) and two distinct points is a constant.
•The fixed points are called the foci of the hyperbola.
•The graph of a hyperbola has two parts, called branches.
• Each part resembles a parabola but is a slightly different shape.
•A hyperbola has two vertices that lie on an axis of symmetry called the transverse axis.
•For the hyperbolas, the transverse axis is either horizontal or vertical.
2 2
2 2
( ) ( )1 , where,
horizontal distance from the center to the box
vertical from the center to the box
distance from the center to the focus
= distance from the center to the vertex o
x h y k
a b
a
b
c
2 2 2
f box
For both vertical and horizontal hyperbolas,
a b c
EQUATION OF HYPERBOLA
GRAPH OF HYPERBOLA
Horizontal Tranverse AxisVertical Tranverse Axis
HORIZONTAL TRANVERSE AXIS
The branches of the hyperbola open left and right
2 2
2 2
( ) ( )1
x h y k
a b
VERTICAL TRANVERSE AXIS
2 2
2 2
( ) ( )1
y k x h
b a
The branches of the hyperbola open up and down.
ASYMPTOTE•The graph of an hyperbola gets fairly flat and straight when it gets far away from its center.
• From the graph, it will look very much like an "X", with maybe a little curviness near the middle.
•These "nearly straight" parts get very close to what are called the asymptotes of the hyperbola.
• For an hyperbola centered at (h, k) and having fixed values a and b, the asymptotes are given by the following equations:
( )b
y x h ka
( )a
y x h kb
Vertical
Horizontal
ECCENTRICITY•Hyperbolas can be fairly straight or else pretty bendy.
•The eccentricity is the ratio of the distance from the center to a focus divided by the distance from the center to a vertex.
•In other words, eccentricity can be defined as the measure of
the amount of curvature is the where
• Bigger values of e correspond to the straighter types of hyperbolas, while values closer to 1 correspond to hyperbolas whose graphs curve quickly away from their centers.
ce
a
EXAMPLE QUESTION
Find the center, vertices, foci, eccentricity,
and asymptotes of the hyperbola with the
given equation, and sketch the graph of
2 2
125 144
y x
SOLUTIONSince the y part of the equation is added, then the center, foci, and vertices will be above and below the center (on a line paralleling the y-axis), rather than side by side.
2 2
2 2 2
From the denominator, we know that
25 and 144
5 12
From equation , we know that 13
Then,
a b
a b
c a b c
ce
a
13
5e
2 2 2 2Since ( 0) and ( 0) then, the center is at ( , ) (0,0)
So, the foci are at (0, 13) and (0,13) and the vertices are at (0,5) and (0, 5)
x x y y h k
Because the y part of the equation is dominant (being added, not subtracted), then the slope of the asymptotes has the a on
top, so the slopes will be
5
12m
Center : (0,0)
Vertices : (0, 5) and (0,5)
Foci : (0,-13) and (0,13)
13Eccentricity,
55
Asymptotes, 12
e
y x
APPLICATION OF HYPERBOLA
•Sonic booms are created when an object exceeds the speed of sound in air
•The shock wave of a sonic boom takes the shape of a cone, and when it intersects the ground, it takes the shape of a hyperbola.
•Every point on the curve is hit at the same time, so everyone on the ground will hear the sound at the same time.
•Another application of hyperbolas involves radio waves.
•When there are two points where radio signals are emitted, the signals form concentric circles intersecting each other.
•The patterns created by the intersecting circles of radio waves form the shapes of hyperbolas.
Definition :
Parabola is the set of all point P(x, y) in the plane that are equidistant from a fixed line L, called the directrix, and fixed point F, called the focus.
CONIC SECTIONS : PARABOLA
•Equation of a parabola
•Squaring both sides and simplifying lead to
x2 = 4py
•Standard form Standard form for the equation of a parabola with focus F(0,p) and directrix y = -p. In like manner, if the directrix and focus are x = -p and F(0,p), respectively, there find the standard form for the equation of the parabola is
y2 = 4px
2 2( )x y p y p
•Technique of graphing
vertex
F(o,p)fokus
y = -p directrix
axis
x2 = 4py, p > 0 x2 = 4py, p < 0
vertex
F(0,p)fokus
y = -p directrixaxis
y2 = 4px, p > 0
F(0,p)
fokus
x = -p
directrix
axis
vertex
y2 = 4px, p < 0
F(0,p)
fokus
x= -p
directrix
axis
vertex
Find the vertex, focus, axis, directrix, and graph of the parabola.
.
EXAMPLE QUESTION
2 4 8 28 0y y x
SOLUTIONIn order to write the equation in one of the standard forms we complete the square in y :
Comparing the last equation with (6) we conclude that the vertex is (-4,2) and that 4p=8 or p=2. From p=2>0, the parabola opens to the right and the focus is 2 units to the right of the vertex at (-2, 2).
The directrix is the vertical line 2 units to the left of the vertex, x = -6. Knowing that the parabola opens to the right from the point (-4,2) also tells us that the graph has intercept.
To find the x-intercept we set y=0 in (7) and find immediately 7
2x
2
2
4 4 8 28 4
( 2) 8( 4)
y y x
y x
The intercept is . To find the y-intercepts we set x= 0 in (7)
and find form the quadratic formula that or
and . The y-intercept are and
7( ,0)
2
2 4 2y 7.66y
3.66y (0,2 4 2)(0,2 4 2)
(-2, 2)
x = -6
(-4, 2)
(y - 2)2 = 8(x+4)
APPLICATION OF PARABOLA
1. Braking Distance Formula
The following table is taken from a Virginia Division of Motor Vehicles Manual and it shows the Reaction Distance, the Braking Distance, and theTotal Stopping Distance at various speeds.The Reaction Distance is the distance that your car travels from the time that the driver sees the need to do so until his foot hits the brake. The braking distance is the distance that the car travels after the brakes are applied until it comes to a stop.The Total Stopping Distance is the sum of the Reaction Distance and the Braking Distance.
2. Heater
Heaters are sold which make use of the relection property of the parabola. The heat source is at the focus and heat is concentrated in parallel rays.
3. Path of a Ball
Gallileo was the first to show that the path of an object thrown in space is a parabola.
4. Antenna of a Radio Telescope All incoming rays parallel to the axis of the parabola are reflected through the focus.
5. Flashlights & Headlights In terms of a car headlight, this property is used to reflect the light rays emanating from the focus of the parabola (where the actual light bulb is located) in parallel rays.
6. Parabolic Reflector
Parabolic reflectors work in much the same way as flashlights and antennas.
7. Path of a Projectile
Galileo Galilei found that all objects thrown form a parabolic path, no matter what. He deduced this by the simple observation of watching objects being thrown. Galileo is responsible for the modern concepts of velocity and acceleration to explain projectile motion that is studied today:A projectile which is carried by a uniform horizontal motion compounded with a naturally accelerated vertical motion describes a path which is a semi-parabola.