Mathematics 11
LE 1 Reviewer
I. True or False.
Write TRUE if the statement is
always true. Otherwise, write FALSE.
1. For any set
A
and
B
, if
B
⊂
A
, then
A
C
⊂
B
C
.
2.
N
is closed under subtraction.
3. For any real number
a
,
a
0
= 1.
4. The set
{-
1
,
0
,
1
}
is closed under multiplica-
tion.
5. For any sets
A
and
B
,
n
(
A
∪
B
) =
n
(
A
)+
n
(
B
).
6.
Q
0
has a multiplicative identity element.
7. If
a, b, c
∈
R
and
ac < bc
, then
a < b
.
8.
π
∈
(
Q
C
-
R
).
9. 3
∈
[(
-∞
,
2)
∪
(4
,
7)]
∩
(0
,
6].
10.
x
2
y
+ 2
y
-
x
-
1
is a degree 3 polynomial.
11.
|
π
-
4
|
=
π
-
4.
12. If
|
x
|
>
0, then
x
is positive.
II. Do as indicated.
1. WriteA, BandCin roster form.
2. Write the following sets in roster form:
(c)A∩B∩C(d) (A∪B)-C(e) (B-A)×C(f)P(A∩C)3. Find the quotient and remainder using long di-vision:
III. Factor completely
.
1. 16
x
4
-
1
2.
x
4
-
7
x
2
y
2
+ 9
y
