Question 1

Perform each operation with complex numbers. Give answers in $a+b i$ form.
(a) $(2+6 i)-(1-3 i)$
(b) $\frac{7+4 i}{1+2 i}$
(c) Simplify $i^{39}$
(d) $-2 i(5-i)^{3}$

Accepted Answer

(a) $1+9 i$
(b) $3-2 i$
(c) $-i$
(d) $-148-220 i$

Question 2

For the quadratic function $P(x)=-3 x^{2}-6 x+9$ do each of the following.
(a) Find the vertex using an analytic method.
(b) Give a comprehensive graph and use a calculator to support your result in part (a).
(c) Find the zeros of $P$ and support your result using a graph for one zero and a table for the other.
(d) Find the $y$-intercept analytically.
(e) State the domain and range of $P$.
(f) Give the interval over which the function is increasing, and the interval over which it is decreasing.

Accepted Answer

(a) $(-1,12)$
(b)
  
(c) $-3 ; 1$
  (d) 9
(e) domain: $(-\infty, \infty)$; range: $(-\infty, 12]$
(f) increasing: $(-\infty,-1]$; decreasing: $[-1, \infty)$

Question 3

(a) Solve the quadratic equation $2 x^{2}+5 x-2=0$ analytically. Give the solutions in exact form.
(b) Graph $P(x)=2 x^{2}+5 x-2$ with a calculator. Use your results in part (a) along with this graph to give the solution set of each inequality. Express endpoints of the intervals in exact form.
(i) $P(x)>0$
(ii) $P(x) \leq 0$

Accepted Answer

(a) $\left\{\frac{-5 \pm 1 \overline{41}}{4}\right\}$
(b)
  (i) $\left(-\infty, \frac{-5-\sqrt{41}}{4}\right) \cup\left(\frac{-5+\sqrt{41}}{4}, \infty\right)$
(ii) $\left[\frac{-5-\sqrt{41}}{4}, \frac{-5+\sqrt{41}}{4}\right]$

Question 4

The width of a rectangular box is 3 times its height, and its length is 2 more than its height. Find the dimensions of the box if its volume is 288 cubic inches.

Accepted Answer

The answer of The width of a rectangular box is...

Question 5

The table gives the high school dropout rate (as a percent of enrollment) in the United States for the years 2002 to 2008. (Source: United States Census Bureau, 2008)
  
(a) Plot the data letting $x=2$ represent 2002, $x=3$ represent 2003, and so on.
(b) Find a function of the form $f(x)=a(x-h)^{2}+k$ that models this data. Let $(4,4.4)$ represent the vertex, and use (7,3.3) to determine the value of $a$.
(c) Use the statistical capability of a graphing calculator to find the best-fitting quadratic function, $g$, for this data. Graph both functions $g$ and $f$ from part (b) in the same window as the data points. Which function is the better fit?

Accepted Answer

The answer of The table gives the high school dropout...

Question 6

(a) Given that $f(x)=x^{6}+x^{5}-10 x^{4}+7 x^{3}-x^{2}+10 x-8$ has 1 as a zero of multiplicity 2,2 as a single zero, and -4 as a single zero, find all other zeros of $f$.
(b) Use the information from part (a) to sketch the graph of $f$ by hand. Give an end behavior diagram.

Accepted Answer

The answer of (a) Given that $f(x)=x^{6}+x^{5}-10 x^{4}+7 x^{3}-x^{2}+10 x-8$...

Question 7

Perform the following for the function defined by $f(x)=4 x^{4}-45 x^{2}-49$.
(a) Find all zeros analytically.
(b) Find a comprehensive graph of $f$, and support the real zeros found in part (a).
(c) Discuss the symmetry of the graph of $f$.
(d) Use the graph and the results from part (a) to find the solution set of each of the following inequalities.
(i) $f(x) \geq 0$
(ii) $f(x)<0$

Accepted Answer

The answer of Perform the following for the function defined...

Question 8

Perform the following for the function defined by $f(x)=3 x^{4}-11 x^{3}+4 x^{2}+13 x-5$.
(a) List all possible rational zeros.
(b) Find all rational zeros.
(c) Use the intermediate value theorem to show that there must be a zero between 0 and 1.
(d) Use Descartes' rule of signs to determine the possible number of positive zeros and negative zeros.
(e) Use the boundedness theorem to show that there is no zero less than -2 and no zero greater than 4 .

Accepted Answer

The answer of Perform the following for the function defined...

Question 9

(a) Use only a graphical method to find the real solutions of $x^{5}+3 x^{4}-5 x^{3}+2 x^{2}-7 x+3=0$.
(b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Accepted Answer

The answer of (a) Use only a graphical method to...

Question 10

Divide.
(a) $\frac{6 x^{4}-9 x^{2}}{3 x}$
(b) $\frac{x^{3}-3 x^{2}+5 x-6}{x-1}$

Accepted Answer

The answer of Divide.
(a) $\frac{6 x^{4}-9 x^{2}}{3 x}$
(b) \(\frac{x^{3}-3 x^{2}+5...

Question 11

Perform each operation with complex numbers. Give answers in $a+b i$ form.
(a) $(-2+4 i)-(3-7 i)$
(b) $\frac{9-7 i}{1-3 i}$
(c) Simplify $i^{57}$
(d) $5 i(3-i)^{2}$

Accepted Answer

The answer of Perform each operation with complex numbers. Give...

Question 12

For the quadratic function $P(x)=-2 x^{2}-4 x+6$ do each of the following.
(a) Find the vertex using an analytic method.
(b) Give a comprehensive graph and use a calculator to support your result in part (a).
(c) Find the zeros of $P$ and support your result using a graph for one zero and a table for the other.
(d) Find the $y$-intercept analytically.
(e) State the domain and range of $P$
(f) Give the interval over which the function is increasing, and the interval over which it is decreasing.

Accepted Answer

The answer of For the quadratic function $P(x)=-2 x^{2}-4 x+6$...

Question 13

(a) Solve the quadratic equation $4 x^{2}+2 x-1=0$ analytically. Give the solutions in exact form.
(b) Graph $P(x)=4 x^{2}+2 x-1$ with a calculator. Use your results in part (a) along with this graph to give the solution set of each inequality. Express endpoints of the intervals in exact form.
(i) $P(x)>0$
(ii) $P(x) \leq 0$

Accepted Answer

The answer of (a) Solve the quadratic equation \(4 x^{2}+2...

Question 14

The length of a rectangular box is 2 times its height, and its width is 5 more than its height. Find the dimensions of the box if its volume is 792 cubic inches.

Accepted Answer

The answer of The length of a rectangular box is...

Question 15

The table gives the number of females who earned bachelor's degrees in the United States (in thousands) for the years 1997 to 2006. (Source: Statistical Abstract of the United States, 2006)
  
(a) Plot the data letting $x=7$ represent $1997, x=8$ represent 1998 , and so on.
(b) Find a function of the form $f(x)=a(x-h)^{2}+k$ that models this data. Let $(7,652)$ represent the vertex, and use $(16,855)$ to determine the value of $a$.
(c) Use the statistical capability of a graphing calculator to find the best-fitting quadratic function, $g$, for this data. Graph both functions $g$ and $f$ from part (b) in the same window as the data points.
Which function is the better fit?

Accepted Answer

The answer of The table gives the number of females...

Question 16

(a) Given that $f(x)=x^{6}-2 x^{5}-13 x^{4}+70 x^{3}-160 x^{2}+184 x-80$ has 2 as a zero of multiplicity 2,1 as a single zero, and -5 as a single zero, find all other zeros of $f$.
(b) Use the information from part (a) to sketch the graph of $f$ by hand. Give an end behavior diagram.

Accepted Answer

The answer of (a) Given that \(f(x)=x^{6}-2 x^{5}-13 x^{4}+70 x^{3}-160...

Question 17

Perform the following for the function defined by $f(x)=4 x^{4}+7 x^{2}-36$.
(a) Find all zeros analytically.
(b) Find a comprehensive graph of $f$, and support the real zeros found in part (a).
(c) Discuss the symmetry of the graph of $f$.
(d) Use the graph and the results from part (a) to find the solution set of each of the following inequalities.
(i) $f(x) \geq 0$
(ii) $f(x)<0$

Accepted Answer

The answer of Perform the following for the function defined...

Question 18

Perform the following for the function defined by $f(x)=3 x^{4}-8 x^{3}-6 x^{2}+17 x+6$.
(a) List all possible rational zeros.
(b) Find all rational zeros.
(c) Use the intermediate value theorem to show that there must be a zero between -2 and -1 .
(d) Use Descartes' rule of signs to determine the possible number of positive zeros and negative zeros.
(e) Use the boundedness theorem to show that there is no zero less than -2 and no zero greater than 4 .

Accepted Answer

The answer of Perform the following for the function defined...

Question 19

(a) Use only a graphical method to find the real solutions of $x^{5}-3 x^{4}-5 x^{3}+6 x^{2}+2 x+3=0$.
(b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Accepted Answer

The answer of (a) Use only a graphical method to...

Question 20

Divide.
(a) $\frac{x^{3}-3 x^{2}+2}{x-1}$
(b) $\frac{x^{4}-2 x^{3}+2 x^{2}-3}{x^{2}+3}$

Accepted Answer

The answer of Divide.
(a) $\frac{x^{3}-3 x^{2}+2}{x-1}$
(b) $\frac{x^{4}-2 x^{3}+2 x^{2}-3}{x^{2}+3}$...

Quiz 3: Polynomial Functions

Perform each operation with complex numbers. Give answers in $a+b i$ form. (a) $(2+6 i)-(1-3 i)$ (b) $\frac{7+4 i}{1+2 i}$ (c) Simplify $i^{39}$ (d) $-2 i(5-i)^{3}$

The width of a rectangular box is 3 times its height, and its length is 2 more than its height. Find the dimensions of the box if its volume is 288 cubic inches.

(a) Given that $f(x)=x^{6}+x^{5}-10 x^{4}+7 x^{3}-x^{2}+10 x-8$ has 1 as a zero of multiplicity 2,2 as a single zero, and -4 as a single zero, find all other zeros of $f$ . (b) Use the information from part (a) to sketch the graph of $f$ by hand. Give an end behavior diagram.

(a) Use only a graphical method to find the real solutions of $x^{5}+3 x^{4}-5 x^{3}+2 x^{2}-7 x+3=0$ . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) $\frac{6 x^{4}-9 x^{2}}{3 x}$ (b) $\frac{x^{3}-3 x^{2}+5 x-6}{x-1}$

Perform each operation with complex numbers. Give answers in $a+b i$ form. (a) $(-2+4 i)-(3-7 i)$ (b) $\frac{9-7 i}{1-3 i}$ (c) Simplify $i^{57}$ (d) $5 i(3-i)^{2}$

The length of a rectangular box is 2 times its height, and its width is 5 more than its height. Find the dimensions of the box if its volume is 792 cubic inches.

(a) Given that $f(x)=x^{6}-2 x^{5}-13 x^{4}+70 x^{3}-160 x^{2}+184 x-80$ has 2 as a zero of multiplicity 2,1 as a single zero, and -5 as a single zero, find all other zeros of $f$ . (b) Use the information from part (a) to sketch the graph of $f$ by hand. Give an end behavior diagram.

(a) Use only a graphical method to find the real solutions of $x^{5}-3 x^{4}-5 x^{3}+6 x^{2}+2 x+3=0$ . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) $\frac{x^{3}-3 x^{2}+2}{x-1}$ (b) $\frac{x^{4}-2 x^{3}+2 x^{2}-3}{x^{2}+3}$

Quiz 3: Polynomial Functions

Perform each operation with complex numbers. Give answers in a+bia+b ia+bi form. (a) (2+6i)−(1−3i)(2+6 i)-(1-3 i)(2+6i)−(1−3i) (b) 7+4i1+2i\frac{7+4 i}{1+2 i}1+2i7+4i​ (c) Simplify i39i^{39}i39 (d) −2i(5−i)3-2 i(5-i)^{3}−2i(5−i)3

The width of a rectangular box is 3 times its height, and its length is 2 more than its height. Find the dimensions of the box if its volume is 288 cubic inches.

(a) Use only a graphical method to find the real solutions of x5+3x4−5x3+2x2−7x+3=0x^{5}+3 x^{4}-5 x^{3}+2 x^{2}-7 x+3=0x5+3x4−5x3+2x2−7x+3=0 . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) 6x4−9x23x\frac{6 x^{4}-9 x^{2}}{3 x}3x6x4−9x2​ (b) x3−3x2+5x−6x−1\frac{x^{3}-3 x^{2}+5 x-6}{x-1}x−1x3−3x2+5x−6​

Perform each operation with complex numbers. Give answers in a+bia+b ia+bi form. (a) (−2+4i)−(3−7i)(-2+4 i)-(3-7 i)(−2+4i)−(3−7i) (b) 9−7i1−3i\frac{9-7 i}{1-3 i}1−3i9−7i​ (c) Simplify i57i^{57}i57 (d) 5i(3−i)25 i(3-i)^{2}5i(3−i)2

The length of a rectangular box is 2 times its height, and its width is 5 more than its height. Find the dimensions of the box if its volume is 792 cubic inches.

(a) Use only a graphical method to find the real solutions of x5−3x4−5x3+6x2+2x+3=0x^{5}-3 x^{4}-5 x^{3}+6 x^{2}+2 x+3=0x5−3x4−5x3+6x2+2x+3=0 . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) x3−3x2+2x−1\frac{x^{3}-3 x^{2}+2}{x-1}x−1x3−3x2+2​ (b) x4−2x3+2x2−3x2+3\frac{x^{4}-2 x^{3}+2 x^{2}-3}{x^{2}+3}x2+3x4−2x3+2x2−3​

Perform each operation with complex numbers. Give answers in $a+b i$ form. (a) $(2+6 i)-(1-3 i)$ (b) $\frac{7+4 i}{1+2 i}$ (c) Simplify $i^{39}$ (d) $-2 i(5-i)^{3}$

(a) Use only a graphical method to find the real solutions of $x^{5}+3 x^{4}-5 x^{3}+2 x^{2}-7 x+3=0$ . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) $\frac{6 x^{4}-9 x^{2}}{3 x}$ (b) $\frac{x^{3}-3 x^{2}+5 x-6}{x-1}$

Perform each operation with complex numbers. Give answers in $a+b i$ form. (a) $(-2+4 i)-(3-7 i)$ (b) $\frac{9-7 i}{1-3 i}$ (c) Simplify $i^{57}$ (d) $5 i(3-i)^{2}$

(a) Use only a graphical method to find the real solutions of $x^{5}-3 x^{4}-5 x^{3}+6 x^{2}+2 x+3=0$ . (b) Based on your answer in part (a), how many nonreal (complex) solutions does the equation have?

Divide. (a) $\frac{x^{3}-3 x^{2}+2}{x-1}$ (b) $\frac{x^{4}-2 x^{3}+2 x^{2}-3}{x^{2}+3}$