1. If π₯ < 0
and π¦ > 0
, determine the sign of the real number.
π₯
π¦
+ π₯
2. Express the statement as an inequality.
The negative of π§ is not greater than 3.
3. Rewrite the number without using the absolute value symbol, and simplify the result.
(a) |4 β π|
(b) |π β 4|
(c) /β2 β 1.5/
4. The two given numbers are coordinates of points π΄
and π΅,
respectively, on a coordinate
line. Express the indicated statement as an inequality involving the absolute value symbol.
4,
π₯;
π(π΄, π΅)
is not greater than 3.
5. Rewrite the expression without using the absolute value symbol, and simplify the result.
|2 β π₯| if π₯ < 2
6. Approximate the real-number expression. Express the answer in scientific notation
accurate to four significant figures.
(a)
!.#Γ!%
!
&.!Γ!%
"
'!.(#Γ!%
!
(b) (1.23 Γ 10
)*
) + β4.5 Γ 10
&
7.
Geometric proofs of properties of real numbers were first given by the ancient Greeks. In
order to establish the distributive property π(π + π) = ππ + ππ
for positive real numbers
π, π,
and π,
find the area of the rectangle shown in the figure in two ways.
8.
Express the number in the form π/π
, where π
and π
are integers.
9
(/#
9. Simplify.
(27π
,
)
)#/&
10. Simplify the expression, and rationalize the denominator when appropriate.
D
5π₯
-
π¦
&
27π₯
#
#
c
c
a
b
11.
Body surface area
A personβs body surface area π
(in square feet) can be approximated by
π = (0.1091)π€
%.*#(
β
%..#(
,
where height β
is in inches and weight π€
is in pounds.
(a) Estimate π
for a person 6
feet tall weighing 175
pounds.
(b) If a person is 5
feet 6
inches tall, what effect does a 10%
increase in weight have on
π?
12. Express as a polynomial.
Kβπ₯ + Lπ¦MKβπ₯ β Lπ¦M
13. Factor the polynomial.
3π₯
&
+ 3π₯
#
β 27π₯ β 27
14. Simplify the expression.
9π₯
#
β 4
3π₯
#
β 5π₯ + 2
β
9π₯
*
β 6π₯
&
+ 4π₯
#
27π₯
*
+ 8π₯
15. Simplify the expression.
3π‘
π‘ + 2
+
5π‘
π‘ β 2
β
40
π‘
#
β 4
16. Simplify the expression.
π₯ + 2
π₯ β
π + 2
π
π₯ β π
17. Rationalize the numerator.
βπ β βπ
π
#
β π
#
18. Simplify the expression.
(π₯
#
β 1)
*
(2π₯) β π₯
#
(4)(π₯
#
β 1)
&
(2π₯)
(π₯
#
β 1)
-
19. Use properties (1), (2) of the negative numbers to prove Property 3:
(βπ)(βπ) = ππ
20.
Prove Property 2 of properties of Quotient.
21. Determine on a coordinate line, the point corresponding to β5
.
22. Prove law 2 of the of the laws of exponent for Real Numbers.
23. Prove law 3 of the laws of Radicals.
24. Prove that π₯
#
+ 1
irreducible over β.
25.
What happens to the quotient
π₯
#
β π
#
π₯ β π
when π₯
is βcloseβ to π?