M(M; 5 61V -=4 24BCNMAB 48PHỬỤNG TRỠNH TIEỎP TUYEỎN CUỶA ( C) TAÙI M0(X0;Y0 )
2) ∀ M ∈ d : M(m; 5 61
V -
=
4 24
BCNMAB
48
Phửụng trỡnh tieỏp tuyeỏn cuỷa ( C) taùi M
0
(x0;y
0
):
5
V = V
Thoỷa YCBT :
.
0,25
3
2
x x
S BCNM
4
BCNMAB
2 7
y x = ( - x
0
2
- x
0
+ 2 )(x
0
0
− − − + + ữ ữ
9 108 128 0
2
2
x ax a
⇔ − + =
0
3 2 3
x = 4a (Nhaọn)
– x
0
)
3
Tieỏp tuyeỏn ủi quaM ⇔
⇔
x = 32a (Loaùi)
m x = (
5 61 2 7
+ − − − + + ữ ữ
4 24 3 2 3
2
KL : x = 4a
- - + )(m – x
0
)
0
0
2
x m x mx m
2 1 3 5 0
Caõu VIa : ( 2 ủieồm )
+ − ữ − + − =
0
0
0