内容正文:
课时7抛物线的方程与性质
F
段
用
@
县
y
C
A
D
不命
AI8
y2=4x
2p=4,p=2
C:y2=4x
4,0)
AB
AB
M
y2=2(x-4)
AB
AB
x=my+4
y2=4x
y2-4my-16=0△=16m2+64>0
A(x1,y),B(x2,y2)
y+y2=4m,3=-16
%=十5=2m,=2m2+4
AB
M(xo2Yo)
2
比。=y4
21
AB
M
4
y2=2(x-4)
A1,m)
C:y2=2px(p>0)
A
C
2
P=
1
-2
A1,m)
2=1+
C
2
P-2
p=2
手
(x-1)2+y2=25
y2=2px(p>0)
F
A
AF
l
(X-1:+V2-25
8-12+12-25
46-30-4-0
:420-24-0
48+3V-4-0
X-4
x=-6
3-2
今
y2=4x
AF =3BF
AB=
8-3
6-3
3-2
y2=4x
(1,0)
x=-1
A(x,y),B(x2,y2)
2=4x,2=4x
AF=3BF
y=3y2
x1=9x2
AF =3BF
x+1=3(x2+1)
x1=3x2+2
y
A
AA=年+1++1=方+无+2=16
3
y2=2pxp>0)
AF BF =2
p=
F(.0)
号
y2=2px
y
-3x+4p=0
△>0,A(x,y),B(x2,y2)
X1+x2=3p
12
=4
1=g+号+号r-+经a+=+号g+)-号=2
1
+号xp+r-2
卫=1
4
A
C y2=2px(p>0)
△FAB
y2=4V2x
y2=8x
y2=4v2x y2=8x
y2=4x
1
∠AFB=
π2
×2p×p=8
2
p=2V2
∠FAB=
π2
1
∠FBA=
p=4
y2=4V2x
y2=8x
F(0,1)
1:y=-1
C
C
x2=4y
C
x
P(x,y)
C
y≥0
P
C
P
d≥2
F(0,1)
1:y=-1
p=2
x2=4y
x2=4y
x2=4y
y≥0
P
C
x2=4y
P
d≥1
AC
〔
C:y2=2px(p>0)
F
1:y=x-1 C A,B
p=2
p=4
|AB=8
FA.FB=-4
()
=1
p=2
2
y2=4x
()()
y
x2-6x+1=0
y=x-1
x+七2=6,xx2=1
AB=x+x2+p=6+2=8
FA=(x-1,),FB=(x2-1,y)
FA·FB=(x-1(x2-1+2
=xx2-(x+)+1+(-1(x2-1=2x62-2(x+x)+2=-8
C:y2=6x
F
F
A B A 1:x=
3
C
D
F
AB
2
1 E
(
AB
I AD-AF
|AE曰HAB
IADAF
A
|AB|≥2p=6
C
3
AB:x=my+
2
A(G)B(x,y2)
D
A
0
3
x=my+
-2
x
y2-6my-9=0
y+y2=6m
yy3=-9
y2=6x
x+x3=m(0y+y2)+3=6m2+3
3,3
|AB=x++x+号=6m2+6
m=0
2
2
E)148=2p=61EFa+=3
AB=6AE AB
B
|AEBE=32,AEI·BE=18
EF:x-
m≠0
2
EF9+9m2
5-4CEsn∠48-号8-号6r+6+,9
in
>18
18
AE BE>18
D
ACD
C:y2=4x
0
tan∠MOF
52
2
P
tan∠MOF=0
P
F1,0)
4
t
tan∠MOF=
2
At
4t=1
2+42+422.4
8
t=2
tan∠MOF
AB
G:y2=2px(p>0)
C
1
AB
F
8
AB
3
G
∠ACB
AB
AB=x+xg+p=8,
A(xayA,B(xg:ya)
X4+XB=3,
2
p=2
y2=4x
AB
(1,0)
c-l年
AB
x=ty+n
x=ty+n
y2=4x
y2-4y-4n=0
△>0
t2+n>0
y+2=4t,yy2=-4n
a-m小-年
∠ACB=90
CA.CB=0
++51+为-(y+为+e2=0
n2+4t2+2n+1-4n-4tc+c2=0
16
(n-1)2+(2t-c)2=0
n=1
AB
(1,0)
C:y2=2px(p>0)
F2
C
y=-2x+2
IAF
1Br:y=-2x+2
y=0
x=1
F(1,0)p=2
C:y2=4x
x=-1
B(-1,4)
y4=4
C:y2=4xx4=4
M=8=x+号4+1-5
O
y2=2px(p>0)
F
C(2p,0
BC
D
CF=AF
3v2
AC
k=
2
-V2y2=4x
C(2n,0
D
C衣
C℉
3卫
AB∥x
CF=AF AB=AF
CF=AB
ABFC
2
CF=AB
3P
3卫
2
CD=BD
22
XA=卫
y2=2px
ya=12p
1
、x×3x2p=2
W2
p=2
y2=4x
to=2g0-5
p-2p
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