35


TRUNG TÂM D Y THÊM

Câu
1

LÊ H NG PHONG

=
(C)
: D = R\{ 1}.
:
y=2

a
*
*
lim

(C).

,

lim

; lim

* y' =



6
5
4
3
2
1
-5 -4 -3 -2 -1
-1
-2

b

y
0.5

x
1

2

3

(C)
(d)

0.25

+
2


)

1 = 4x0 + 4

(d): y =

(

2

0.25

2x0 = 8

)

=

.

: I=

(

)

I=

x0 = 4

= ex.

0.25

36


TRUNG TÂM D Y THÊM

LÊ H NG PHONG

I2 =

=

= 1.

=e
3

1 + 1 = e.
:
3sinx + cos2x = 2 (1)
2
2sin x + 3sinx = 2
2sin2x 3sinx + 1 = 0

a
1



(1)
0.25

: log3x

t

2.

2

x

0.25
9.

.

2

4

,

>0

a

0.5

.

=

=

)!

0.25

.( ) .

2

.

.

k = 9.
2

trong khai tri

0.25
.

( ).

8
.

:

0.25


38


TRUNG TÂM D Y THÊM

LÊ H NG PHONG

= (A; B)
(A2 + B2 > 0)
CD: A(x + 3) + B(y + 3) = 0
Ax + By + 3A + 3B = 0.

A

B

M

0.25
D

C

: SBCD = SACD = 18
d(A; CD) =

;

)

3y 6 = 0

D(3d + 6; d)

(d + 3)2 = 9
d = 0 hay d = 6
(6; 0)
A(0; 2)

0.25

B( 3; 1).

= 27

;

A = 31
(

CD: 31x

27y + 12 = 0

(



.

: (2)

(3)

=

.

: (3)

Khi x =
*

1.0

( )

2t = t

(

)

(

)


39

= 2, y = 0
.

.
0.25


TRUNG TÂM D Y THÊM

9

LÊ H NG PHONG
2

Cho x,
P= (
*

(
* 4 = (12 + 12)(x2 + y2)
3

3

1.0

)


.

)

0.25
3

.

3

x +y

2.

.

;

:
= (x2 + y2)3 = x6 + y6 + 3x2y2(x2 + y2)
= x6 + y6 + 6x2y2 = (x3 + y3)2 2x3y3 + 6x2y2
2x3y3 6x2y2 = t2 8
* 2(x3 + y3) = (x3 + y3)(x2 + y2) = x5 + y5 + x2y3 + x3y2 = x5 + y5 + x2y2(x + y)
x5 + y5 + x2y2(x + y) = 2t.
*2

P

3


2t2 + 10t + 16 = f(t).

.

: f(2) = 28;

.

()

( )

0.25

()

;

;

40

.