Các em hãy làm quen với các bài toán bằng tiếng Anh sau đây.. Chúc các em học tốt.. The tangents TA and TD are drawn from a point T to the circle, centre O.. The diameter DB and the tang
Trang 1Các em hãy làm quen với các bài toán bằng tiếng Anh sau đây Chúc các em học tốt.
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1 (a) It is given that = {1, 2, 3, 4, 5, , k} where k is a positive integer.} where k} where k is a positive integer is a positive integer.
P is a subset where P = {x: x is a prime number}
Q is another subset and Q = {x: the unit digit is 9}
(i) List all the members of Q given that k} where k is a positive integer = 100
(ii) If n(P Q) = 4, list the elements of the set P Q and hence state the largest possible value of k} where k is a positive integer
(b) It is given that n() = 23, n(A B) = x, n(A) = y, n(B) = 2y and n(A' B') = 7
(i) Use a Venn diagram and show that 3y = 16 + x
(ii) Hence find the least possible value of y
2 Find the equation of the perpendicular bisector of AB where A is (3, 10) and B is (7, 2)
3 The roots of the quadratic equation x2 - 6x + x = 0 are and
Without using a calculator, show that
1
+ 1 = 3
4 The tangents TA and TD are drawn from a point T to the circle, centre O The diameter
DB and the tangent TA when produced meet at E Given that ADO = 26o, find
(a) ADT
(b) ATD
(c) BAE
(d) ACD ( C is a point on the cirlce, centre O)
Tôn Nữ Bích Vân giới thiệu
Trang 21 (a) (i) Q = {9, 19, 29, 39, 49, 59, 69, 79, 89, 99}
(ii) P Q = {19, 29, 59, 79} ; k} where k is a positive integer = 88 (b)
least value of y = 6 [when x = 2]
2 The mid-point of AB is (5, 6) The gradient of the line AB is 27--103 = -2 The perpendicular is the
line with gradient 21 and passing through the
point (5, 6) Equation of the perpendicular of AB is:
y - 6 =
2
1
(x - 5)
y = 21 x +
2 7
Alternative method
Let P(x, y) lie on the perpendicular of AB
Therefore PA = PB
(x - 3) 2 (y - 10) 2 = (x - 7) 2 (y - 2) 2
x2 - 6x + 9 + y2 - 20y + 100 = x2 - 14x + 49 + y2 - 4y + 4
Simplifying, 8x - 16y + 56 = 0
2
7
3 The quadratic equation whose roots are and is (x - ) (x - ) = 0
x2 - ( + )x + = 0
By inspection: + = 6
= 2
2
6 1
1
4 (a) ODT = 90o (tan rad )
ADT = 90o - 26o
= 64o (b) TA = TD (tangents from an external point)
TDA = TAD (base s of isos )
ATD = 180o - 64o - 64o ( sum of )
= 52o (c) BAE = ADB ( in alt segment) = 26o
7
(y-x) x (2y-x)
26 o
O
E
A B
C
D
T
Trang 3(d) ACD = ADT ( in alt segment) = 64o