![]()
MATH
140 -- Intermediate Algebra -- Exercise Solutions
Section: 5.3
2)
The degree of 7 is 0. (Because
it is 7x0)
4)
The degree of - z3 is 3 (Because
the exponent on the variable is 3)
6) The degree of 12x3z is 4 (Because the sum of the exponents on the variables is 3 + 1 =4)
8) The polynomial 7x - 8 is a binomial of degree 1. (It is a binomial because it has two terms and it has degree 1 because the term with largest degree has degree 1 -- the other term has degree 0).
10) The polynomial 5x2 - 3x2y - 2x3 is a trinomial with degree 3. (It is a trinomial because it has three terms and it has degree 3 because the term with largest degree has degree 3 -- the first term has degree 2, the second term has degree 2+1 =3 and the third term has degree 3).
12) The polynomial - 9 is a monomial (one term) and it has degree 0 (because it is -9x0).
14) The
polynomial - 2x2y - 3y2 + 4x + y5 is neither
a monomial, binomial, nor a trinomial(it has
four terms).
The degree of - 2x2y - 3y2 + 4x + y5 is 5.
(The degree of the term terms with the largest
degree -- The first term has degree 3, the second term has degree 2, the third
term has degree1 and the last term has degree 5).
15)
In your own words, describe how to find the degree of a term.
Dispite what the
author might say, there is ONLY ONE correct response to this question and
it MUST be the Definition of the degree of a term.
So the correct response is:
Definition:
The degree of a term is the sum of the exponents on the variables.
16)
In your own words, describe how to find the degree of a polynomial.
Dispite what the
author might say, there are ONLY TWO correct responses to this question.
The most direct response MUST be the Definition
of the degree of a polynomial.
Definition:
The degree of a a polynomial is the degree of the leading term.
However, contained
in this definition is the definition of leading term.
Definition:
The leading term of a polynomial is the term with largest degree.
In view of the definiton of leading term
one might say that the degree of a polynomial is the degree of the term with
largest degree.
18) If
the rule for a function named Q is given by the equation Q(x) = 5x2
- 1, find Q(4).
Solution: Note
that Q(4) is the unique range element associated with the domain element 4
by the function named Q.
Note
that the rule for Q states that one finds the range element associated with
a particular domain element by squaring the domain element, multiplying that
square by 5 and then subtracting 1. All of this can be easily accomplished
by substituting the domain element 4 into the rule so that we obtain
Q(4) = 5(42) - 1 = 5(16)
- 1 = 79
20) If
the rule for a function named P is given by the equation Q(x) = x2
+ x + 1, find P(- 4).
Solution: Note
that P(- 4)is the unique range element associated with the domain element
- 4 by the function named P.
Note
that the rule for P states that one finds the range element associated with
a particular domain element by squaring the domain element, adding the domain
element to that square and then adding 1. All of this can be easily
accomplished by substituting the domain element - 4 into the rule so that
we obtain
P(- 4) = (- 4)2 + (-
4) + 1 = 16 - 4 + 1= 13
22) If
the rule for a function named Q is given by the equation Q(x) = 5x2
- 1, find Q(0).
Solution: Note
that Q(0) is the unique range element associated with the domain element 0
by the function named Q. Note also that the point (0, Q(0)) is the y-intercept
of the graph of Q.
Note
that the rule for Q states that one finds the range element associated with
a particular domain element by squaring the domain element, multiplying that
square by 5 and then subtracting 1. All of this can be easily accomplished
by substituting the domain element 4 into the rule so that we obtain
Q(0) = 5(02) - 1 = 5(0)
- 1 = -1
24) If
the rule for a function named P is given by the equation Q(x) = x2
+ x + 1, find P(1/2).
Solution: Note
that P(1/2)is the unique range element associated with the domain element
1/2 by the function named P.
Note
that the rule for P states that one finds the range element associated with
a particular domain element by squaring the domain element, adding the domain
element to that square and then adding 1. All of this can be easily
accomplished by substituting the domain element - 4 into the rule so that
we obtain
P(1/2) = (1/2)2 + (1/2)
+ 1 = 1/4 +1/2 + 1= 1/4 + 2/4 +4/4 = 7/4
26)
If the rule for a function named h is given by the equation h(x) = -16t2
+ 1053, find h(4).
Solution: Note that
h(4) is the unique range element associated with the domain element 4 by the
function h.
Note
that the rule for h states that one finds the range element associated with
a particular domain element by squaring the domain element, multiplying that
square by - 16 and then adding 1053. All of this can be easily accomplished
by substituting the domain element - 4 into the rule so that we obtain
h(4) = - 16(42) + 1053
= - 256 + 1053 = 797
