math placement exam materials and practice exam

20
Placement Test Practice Materials What’s here: 1. Placement Exam Topic List—to help you know what types of things might be on the placement test. This list is not comprehensive, but will help you get a handle on what types of topics might be included and what kinds of skills will be expected. 2. Mathematics Placement Practice Test—to help you get a feeling for the terminology and wording of problems that could be posed on the test. None of these are actual test problems, but they have the same flavor as the problems on the test. It is important to note that the practice test has only 15 questions, whereas the actual test has 25 questions that you must complete in half an hour. Therefore, you must complete the 15 practice test questions in 18 minutes if you are trying to get a sense of how fast you must work on the actual test. Calculators and reference books or notes, including formulas, are not allowed on the actual placement exam. If you want to simulate the experience of taking the placement exam, do not use these on the practice exam. 3. Mathematics Placement Practice Test Answers—to help you score your practice test. 4. Mathematics Placement Practice Test Solutions—to help you understand the answers to the Practice Test. Full solutions are provided for each problem. Further, each problem is identified with the corresponding topics it covers from the Placement Exam Topic list. Recommendation on how to use the materials: If you are mainly concerned about language, but not mathematics. Read through the Placement Exam Topic List. Try to learn the American English words for the mathematics that you know by looking at the diagrams and formulas. Do not hesitate to look up mathematical terms on www.wikipedia.org/ or mathworld.wolfram.com/. Both are fine for most mathematics. Take the Placement Practice Test. Score your practice test, noting which problems you missed because of the math and which problems you missed because of the wording. For all problems that you missed, be sure to examine the Practice Test solutions. Think about the problems that you missed because of wording separately. Now that you can see the solutions, do you better understand the meaning? Would you understand the meaning in another similar situation? Why or why not? Try to pose similarly worded mathematical questions.

Upload: amanda-carls

Post on 30-Mar-2016

242 views

Category:

Documents


3 download

DESCRIPTION

Needing to take the Math Placement Exam at Summer Orientation? View this document from the Math Department to see which topics to study to help you prepare for the exam. A 15-question practice exam (starting on pg. 9) will be similar to what you will complete at Summer Orientation.

TRANSCRIPT

Placement  Test  Practice  Materials    

What’s  here:  1. Placement  Exam  Topic  List—to  help  you  know  what  types  of  things  might  be  

on  the  placement  test.    This  list  is  not  comprehensive,  but  will  help  you  get  a  handle  on  what  types  of  topics  might  be  included  and  what  kinds  of  skills  will  be  expected.  

2. Mathematics  Placement  Practice  Test—to  help  you  get  a  feeling  for  the  terminology  and  wording  of  problems  that  could  be  posed  on  the  test.    None  of  these  are  actual  test  problems,  but  they  have  the  same  flavor  as  the  problems  on  the  test.      

⎯ It  is  important  to  note  that  the  practice  test  has  only  15  questions,  whereas  the  actual  test  has  25  questions  that  you  must  complete  in  half  an  hour.    Therefore,  you  must  complete  the  15  practice  test  questions  in  18  minutes  if  you  are  trying  to  get  a  sense  of  how  fast  you  must  work  on  the  actual  test.  

⎯ Calculators  and  reference  books  or  notes,  including  formulas,  are  not  allowed  on  the  actual  placement  exam.    If  you  want  to  simulate  the  experience  of  taking  the  placement  exam,  do  not  use  these  on  the  practice  exam.  

3.  Mathematics  Placement  Practice  Test  Answers—to  help  you  score  your  practice  test.  

4. Mathematics  Placement  Practice  Test  Solutions—to  help  you  understand  the  answers  to  the  Practice  Test.    Full  solutions  are  provided  for  each  problem.    Further,  each  problem  is  identified  with  the  corresponding  topics  it  covers  from  the  Placement  Exam  Topic  list.  

 Recommendation  on  how  to  use  the  materials:    If  you  are  mainly  concerned  about  language,  but  not  mathematics.    

• Read  through  the  Placement  Exam  Topic  List.    Try  to  learn  the  American  English  words  for  the  mathematics  that  you  know  by  looking  at  the  diagrams  and  formulas.      

• Do  not  hesitate  to  look  up  mathematical  terms  on  www.wikipedia.org/ or mathworld.wolfram.com/ . Both are fine for most mathematics.  

• Take  the  Placement  Practice  Test.  • Score  your  practice  test,  noting  which  problems  you  missed  because  of  the  

math  and  which  problems  you  missed  because  of  the  wording.  • For  all  problems  that  you  missed,  be  sure  to  examine  the  Practice  Test  

solutions.    Think  about  the  problems  that  you  missed  because  of  wording  separately.    Now  that  you  can  see  the  solutions,  do  you  better  understand  the  meaning?    Would  you  understand  the  meaning  in  another  similar  situation?    Why  or  why  not?    Try  to  pose  similarly  worded  mathematical  questions.    

If  you  are  mainly  concerned  with  brushing  up  on  mathematics,  but  not  with  understanding  English.  

• Read  through  the  Placement  Exam  Topic  List.    Mark  the  topics  that  you  do  not  recall  how  to  do  and/or  the  formulas  and  identities  that  you  do  not  recall.      

• Write  all  formulas  and  identities  you  need  to  memorize  on  a  small  piece  of  paper  or  an  index  card.    Carry  this  around  with  you,  looking  at  it  every  5  minutes  or  so  to  quiz  yourself  on  what  is  written  there.    You  should  be  working  towards  being  able  to  recall  everything  on  the  card  verbatim  with  your  eyes  closed.    (You  may  wish  to  make  flash  cards  instead.)    By  the  way,  you  want  this  in  long-­‐term  memory  storage,  not  just  in  “until  after  I  take  the  placement  test”  storage,  as  you  will  be  expected  to  know  these  formulas  and  identities  in  subsequent  courses.  

• For  the  topics  you  do  not  remember  how  to  do,  you  have  a  number  of  options.

o  Go  to  your  local  library  and  check  out  the  appropriate  level  math  book  for  self-­‐study,  

o Try  to  buy  a  book  at  a  book  store  to  help  you,   o Use  targeted  mini-­‐lectures  on  the  web,  one  popular  website  is:  

https://www.khanacademy.org,  or   o Use  pre-­‐made  courseware  on  the  web,  one  such  website  is:    

http://www.saylor.org/majors/math/  .

If  you  don’t  know  the  mathematics,  you  should  take  the  appropriate  course  rather  than  trying  to  learn  it  on  your  own  and  place  into  an  inappropriately  high  course.    Knowingly  placing  yourself  too  high  or  too  low  will  undercut  your  ability  to  thrive  in  your  mathematics  course  and  will  waste  your  semester.    Help  yourself  have  a  great  mathematical  experience  in  the  Mercer  Math  Department  with  our  committed  faculty  by  placing  yourself  correctly.    We  look  forward  to  getting  to  know  you!      

Mathematics  Placement  Exam  Topic  List    The  mathematics  placement  exam  emphasizes  topics  from  algebra,  geometry,  pre-­‐calculus,  and  trigonometry.      For  full  understanding  of  the  Mercer  Math  courses  resting  upon  the  knowledge  from  these  subjects,  please  do  not  assume  that  you  will  only  need  to  know  the  limited  number  of  concepts  inventoried  below.    Some  student  learning  objectives  from  Algebra,  Geometry,  Pre-­‐calculus,  and  Trigonometry  that  might  be  tested  on  the  Mathematics  Placement  Exam  are  listed  below.    This  list  does  not  promise  to  be  comprehensive.    Others  may  categorize  the  objectives  into  different  courses.      Please  note  that  formulas  are  not  given  on  the  placement  test.    They  are  to  be  memorized  or  internalized.  For  each  of  the  following,  students  will  know  how  and  be  able  to  accurately:    Algebra    

1. Solve  an  equation  to  find  the  value  of  a  variable.  2. Graph  the  equation  of  a  line.  3. Find  the  slope  of  a  line.  4. Explain  how  the  slope  of  a  line  relates  to  the  appearance  of  a  line.  

a. A  line  with  zero  slope  is  horizontal  (e.g.,  y=7)  b. A  line  with  infinite  slope  is  vertical  (e.g.,  x=2)  c. A  line  with  positive  slope  could  be  described  as  increasing  as  one  

moves  to  the  right  or  it  could  be  described  as  rising  to  the  right  (e.g.,  y-­‐3=5(x-­‐4)    or  y=5x-­‐17  or  2y-­‐10x+34=0.)  

d. A  line  with  negative  slope  could  be  described  as  decreasing  as  one  moves  to  the  right  or  it  could  be  described  as  falling  to  the  right  (e.g.,  y-­‐1=-­‐2(x+1)  or  y=-­‐2x+3  or  5y+10x=15.)  

5. Find  the  intersection  of  two  lines.  a. Report  the  intersection  point.  b. Report  only  the  x-­‐coordinate  of  the  intersection.  c. Report  only  the  y-­‐coordinate  of  the  intersection.  

6. Solve  inequalities  involving  quadratic  functions.  7. Solve  an  inequality  with  absolute  values.  8. Find  the  distance  between  two  points  in  the  Cartesian  plane.  9. Simplify  or  expand  an  expression  with  exponents,  including  fractional  and  

negative  exponents.  10. Understand  the  role  of  exponents  in  working  with  numbers./Have  number  

sense  when  it  comes  to  exponents.  11. Factor  algebraic  expressions.  12. Evaluate  a  function  at  a  given  value.  13. Read,  interpret,  set  up,  and  solve  a  basic  word  problem.  

     

Geometry  

 1. Use  the  formulas  for  perimeters  of  standard  shapes.  

a. A.    Square:    perimeter=4s  b. B.    Rectangle:    perimeter=2x+2y  c. C.    Circle:    perimeter= 2πr  d. D.    Triangle:    perimeter=a+b+c  

2. Use  the  formulas  for  areas  of  standard  shapes.  a. A.    Square:    area=  s2  b. B.    Rectangle:    area=xy  c. C.    Circle:    area=πr2  d. D.    Triangle:      area=(1/2)bh  

ac

b

h

s x

ysA. B.

C. D.r

 3. Use  the  formulas  for  surface  areas  of  standard  shapes.  

a. E.    Box  with  all  6  sides:    Surface  Area  (SA)  =  2lw  +  2wh  +  2lh  b. E.    Box  with  open  top,  but  closed  bottom:      

Surface  Area  (SA)  =  lw  +2wh  +  2lh  c. G.    Sphere:    Surface  Area  (SA)  =  4πr2  d. H.  Cylinder  with  both  bases:    Surface  Area  (SA)  =  2πr2+2πrh  e. H.  Cylindrical  side,  no  bases:    Surface  Area  (SA)=  2πrh  f. Students  are  not  expected  to  know  the  surface  area  of  a  cone  given  

only  the  height  and  base  radius.  4. Use  the  formulas  for  volumes  of  standard  shapes.  

a. E.  Box:    Volume  =  lwh  b. F.    Cone:    Volume  =  (1/3)πr2h  c. G.    Sphere:    Volume  =  (4/3)πr3  d. H.  Cylinder:    Volume  =  πr2h  

5. Reason  using  geometric  logic,  such  as  by  using  proportions.    Pre-­‐Calculus  

1. Recognize  the  use  of  or  employ  the  laws  of  exponents.    For  c,d,g    real  numbers  and  a,b  >  0,  x,y  variables  taking  on  real  values,    

a. cd+g=cdcg     and   ax+y=axay    b. 𝑐!!! = !!

!!   and   𝑎!!! = !!

!!    

c. 𝑐! ! = 𝑐!"and   𝑎! ! = 𝑎!"  d. cgdg=(cd)g  and    axbx=(ab)x  

w

h

l

E.

r

h

F.

G. H.

r

r

h

2. Solve  exponential  growth  problems,  which  might  be  presented  as  word  problems.  Contexts  may  include  banking,  population  growth  or  decay,  or  radioactive  decay.  

3. Recognize  the  use  of  or  employ  the  laws  of  logarithms.    For  c,d,g    positive  real  numbers  and  a,b  >  0,  x,y  variables  taking  on  positive  real  values,    

a. logc(dg)  =  logcd  +  logcg      and  loga(xy)  =  logax  +  logay    b. logc(d/g)  =  logcd  –  logc  g  and  loga(x/y)=  logax  -­‐  logay    c. logc(dg)  =  g(logcd)  and    loga(xb)  =  b(logax)  

4. Realize  that  logarithms  and  exponential  functions  in  the  same  base  are  inverse  functions  and  exploit  that  to  simplify  and  solve  equations.  (I.e.,  loga(ax)=x.)  

5. Solve  logarithmic  equations,  which  might  be  presented  as  word  problems.    These  problems  are  often  part  of  what  originally  seem  to  be  exponential  growth  problems.  

6. Recognize  and  sketch  the  graphs  of  standard  functions  such  as  lines,  power  functions  (x2,  x3,  x-­‐1,  x-­‐2,  xn,  etc.  and  multiples  of  these),  exponential  functions,  and  logarithmic  functions,  all  with  variations.  

7. Understand  the  role  of  transformations  on  graphs  and  determine  the  graph  of  a  function  as  the  transformation  of  a  standard  graph  using  the  algebraic  expression  of  the  function.  

8. Solve  for  the  zeros  of  polynomials  and  rational  functions.  9. Find  the  domain  of  rational  and  root  functions.    Trigonometry  1. Understand  the  meanings  of  period  and  amplitude  of  a  function  both  

graphically  and  algebraically.  

 2. Use  the  six  trigonometric  (trig)  functions  via  their  definitions:        

a. sine:    sin 𝜃 = !!  

b. cosine:    cos 𝜃 = !!  

c. tangent:    tan 𝜃 = !!  

d. cosecant:    csc 𝜃 = !!  

e. secant:    sec 𝜃 = !!  

f. cotangent:    cot 𝜃 = !!  

3. Use  the  definitions  of  the  trig  functions  to  reduce  trigonometric  expressions  

x

y

h

O

   und=undefined;  deg=degrees,  rad=radians  Θ  deg  

Θ  rad  

x   y   sin(θ)  

cos(θ)  

tan(θ)  

csc(θ)  

sec(θ)  

cot(θ)  

0   0   1   0   0   1   0   und   1   und  30   π/6   𝟑

𝟐  𝟏𝟐  

𝟏𝟐  

𝟑𝟐  

13   2   2

3   3  

45   π/4   𝟐𝟐  

𝟐𝟐  

𝟐𝟐  

𝟐𝟐  

1   2   2   1  

60   π/3   𝟏𝟐  

𝟑𝟐  

𝟑𝟐  

𝟏𝟐  

3   23   2   1

3  

90   π/2   0   1   1   0   und   1   und   0  120  

2π/3   −12  

32  

32  

−12  

− 3   23   -­‐2   −1

3  

135  

3π/4   − 22  

22  

22  

− 22  

-­‐1   2   − 2   -­‐1  

150  

5π/6   − 32  

12  

12  

− 32  

−13   2   −2

3   − 3  

180  

π   -­‐1   0   0   -­‐1   0   und   -­‐1   und  

210  

7π/6   − 32  

−12  

−12  

− 32  

13   -­‐2   −2

3   3  

O

1-1

(x,y)

225  

5π/4   − 22  

− 22  

− 22  

− 22  

1   − 2   − 2   1  

240  

4π/3   −12  

− 32  

− 32  

−12  

3   −23   -­‐2   1

3  

270  

3π/2   0   -­‐1   -­‐1   0   Und   -­‐1   und   0  

300  

5π/3   12  

− 32  

− 32  

12  

− 3   −23   2   −1

3  

315  

7π/4   22  

− 22  

− 22  

22  

-­‐1   − 2   2   -­‐1  

330  

11π/6   32  

−12  

−12  

32  

−13   -­‐2   2

3   − 3  

360  

2π   1   0   0   1   0   und   1   Und  

-­‐30   -­‐π/6  =11π/6  

32  

−12  

−12  

32  

  -­‐2   23   − 3  

etc.                      

4. Use  values  of  the  trig  functions  at  the  standard  angles  (in  radians)  and  their  multiples  to  evaluate  trigonometric  expressions  without  a  calculator.    (Students  should  be  able  to  find  the  value  of  any  of  the  six  trig  functions  at  any  standard  angle  based  on  having  memorized  the  value  of  the  functions  sin(θ)  and  cos(θ)  at    x=0,  x=π/6,  x=π/4,  x=π/3,  and  x=π/2.    These  are  the  bolded  entries  in  the  table.)  

5. Graph  the  six  trigonometric  functions  and  their  algebraic  transformations.  6. Use  the  double  and  half  angle  fomulas  for  sine  and  cosine.  

a. sin(2θ)  =  2sin(θ)cos(θ)  b. cos(2θ)  =  cos2(θ)-­‐sin2(θ)  =  2  cos2(θ)  –  1  =  1  -­‐  2sin2(θ)  c. sin! 𝜃 = !!!"#  (!!)

!  

d. cos! 𝜃 = !!!"#  (!!)!

 7. Use  the  main  trig  identities  and  their  variants  that  arise  from  moving  terms  

from  one  side  of  the  equality  to  the  other  through  subtraction.  a. sin2θ  +  cos2θ  =  1  b. tan2θ  +  1  =  sec2θ  c. 1  +  cot2θ  =  csc2θ  d. sin(-­‐θ)  =  -­‐sin(θ)  e. cos(-­‐θ)  =  cos(θ)  f. tan(-­‐θ)  =  -­‐tan(θ)  g. sin !

!− 𝜃 = cos 𝜃  

h. cos !!− 𝜃 = sin 𝜃  

 

Mathematics  Placement  Practice  Test  (The  actual  test  has  radio  buttons  for  multiple  choice  selections,  25  questions,    and  allows  exactly  30  minutes  for  completion.    No  calculators  are  allowed.)    

1. What  is  the  y-­‐coordinate  of  the  intersection  point  of  the  two  lines  given  by  the  equations:  

y=3x-­‐2     and     y=5x+6  a. 4  b. -­‐4  c. 14  d. -­‐14  e. 10  

2. In  a  standard  coordinate  system,  the  graph  of  7y+2x=15  is  a. A  horizontal  line  b. A  vertical  line  c. A  line  rising  to  the  right  d. A  line  falling  to  the  right  e. A  single  point  

3. A  box  has  a  square  base.    The  height  of  the  box  is  three  times  its  width.    If  the  volume  of  the  box  is  3000  cm3,  what  is  the  width  of  the  box?  

a. 10  or  -­‐10  b. 10  only  c. 300  d. 500  e. 3000!  

4. The  area  of  a  triangle  is  81  inches  squared.  Its  base  is  half  its  height.    What  is  the  height  of  the  triangle?  

a. !!  

b. 9  c. 9 2  d. 18  e. !"

!  

5. Suppose  that  the  number  of  cells  in  a  petri  dish  is  600  one  hour  after  the  cells  are  plated  into  the  dish.    Three  hours  after  being  plated  the  cell  population  has  grown  to  3000.    If  the  population  of  cells  in  the  petri  dish  is  growing  exponentially,  what  is  the  number  of  cells  in  the  dish  7  hours  after  they  were  plated?  

a. 725  b. 7800    c. 600 5! !

 d. 75,000  e. 600(2400)3  

   

6. A  function  is  said  to  have  period  B  if  f(x+B)=f(x)  for  all  values  of  x,  and  B  is  the  smallest  such  positive  number.    What  is  the  period  of  the  graph  shown  below?    

   a.  0.2π  b.  0.4π  c.  0.5π  d.  0.8π  e.  2π  

7. The  inequality  0 < 3𝑥 + 2 < 𝑑  is  equivalent  to    a. 𝑥 < !!!

!  

b. –!!!!

< 𝑥 < !!!!  

c. –!!!!

< 𝑥 < !!!!    

d. –!!!!

< 𝑥 < !!!!    and  𝑥 ≠ !!

!    

e. 𝑥 < –!!!!  or  !!!

!< 𝑥  

8. Find  interval(s)  on  which  5x2-­‐9x+2  >0.  a. −2 < 𝑥 < !

!  

b. 𝑥 < −2  and  !!< 𝑥  

c. !! !"!"

< 𝑥 < !! !"!"

 

d. 𝑥 < !! !"!"

and  !! !"!"

< 𝑥  e. The  function  5x2-­‐9x+2  is  always  positive.  

             

-1.5π -π -0.5π 0 0.5π π 1.5π

-3

-2

-1

1

2

3

 9. Find  the  distance  between  points  P  and  Q  in  the  following  figure.  

 a. 2  b. 5  c. 3.5  d. 13  e. 5  

10. At  which  value  of  θ,  0 ≤ θ ≤ !!  ,  does  csc(θ)  =  2?    

a. 0  b. !

!  

c. !!  

d. !!  

e. !!  

11.  If  log3(2x+5)=4,  then  x=  a. 4.5  b. 29.5  c. 35.5  d. 38  e. 43  

12. Let  𝑔 𝑡 = 2𝑡 − 3.    Find  ! !!! !!(!)!

.    Choose  the  most  reduced  answer.  a. -­‐1  b. !

! !  

c. 𝑡 − 1  d. !!!!! !!!!

!  

e. !!!!! !!!!!

 

-1 0 1 2 3 4 5 6

1

2

3

4

P

Q

13. A  function,  f,    is  increasing  on  an  interval  (a,b)  if  for  x,y  in  (a,b)  with  x<y,  f(x)<f(y).    Determine  the  x-­‐interval(s)  on  which  the  pictured  graph  is  increasing.

 a. (-­‐6,-­‐2)  b. (-­‐2,2)  c. (2,6)  d. (-­‐6,-­‐2)  and  (2,6)  e. Only  the  points  x=-­‐2  and  x=2  

14. Which  of  the  following  best  represents  the  graph  of  𝑦 = 2− 𝑒!!!?  

a.  

-6 -4 -2 0 2 4 6

-2

2

-5 -4 -3 -2 -1 0 1 2 3 4 5

-3

-2

-1

1

2

3

b.    

c.  

-5 -4 -3 -2 -1 0 1 2 3 4 5

-3

-2

-1

1

2

3

-5 -4 -3 -2 -1 0 1 2 3 4 5

-3

-2

-1

1

2

3

d.    

e.      

             

-5 -4 -3 -2 -1 0 1 2 3 4 5

1

2

3

4

5

6

-5 -4 -3 -2 -1 0 1 2 3 4 5

-3

-2

-1

1

2

3

15. A  cylinder  in  which  the  radius  equals  the  height  contains  one  largest  possible  sphere.    How  much  volume  is  inside  of  the  cylinder,  but  outside  of  the  sphere?    Because  r=h,  give  your  answer  in  terms  of  r.  

 a.!!𝜋𝑟!  

b.!!𝜋𝑟!  

 c.!!𝜋𝑟!  

d.!!𝜋𝑟!  

e.  There  is  not  enough  information  to  answer  this  question.  

Mathematics  Placement  Practice  Test  Answers:    

1. d  2. d  3. b  4. d  5. d  6. b  7. d  8. d  9. d  10. b  11. d  12. e  13. b  14. a  15. d  

 

Mathematics  Placement  Practice  Test  Solutions  The  letter  answer  from  the  practice  test  is  in  parentheses  after  the  solution.  The  corresponding  topics  from  the  mathematics  placement  exam  topic  list  are  listed  after  that.    

1. What  is  the  y-­‐coordinate  of  the  intersection  point  of  the  two  lines  given  by  the  equations:  

y=3x-­‐2     and     y=5x+6  In  order  for  the  two  lines  to  intersect,  the  x-­‐  and  y-­‐coordinates  must  be  simultaneously  equal.    Because  both  equations  are  currently  written  in  terms  of  y,  we  may  set  the  other  sides  equal  to  each  other:  

    3x-­‐2=5x+6  and  solve  for  x:                    x=-­‐4.    Plugging  back  into  either  equation  to  solve  for  y,  yields    

             y=3(-­‐4)-­‐2=5(-­‐4)+6=-­‐14.    Therefore,  we  report  that  the  y-­‐coordinate  of  the  intersection  point  is  -­‐14.  (d)  Algebra  1,5  

2. In  a  standard  coordinate  system,  the  graph  of  7y+2x=15  is  the  same  as  the  graph  of  the  line  written  in  y=mx+b  form,  which  is  y=(-­‐2/7)x+(15/7).    In  this  form,  we  see  that  the  slope  is  -­‐2/7.    Because  the  slope  is  negative,  the  line  falls  to  the  right.  (d)  Algebra  2,3,4  

3. A  box  has  a  square  base.    The  height  of  the  box  is  three  times  its  width.    If  the  volume  of  the  box  is  3000  cm3,  what  is  the  width  of  the  box?  The  volume  of  a  box  is  length  times  width  times  height.    In  this  case,  length  and  width  are  equal,  because  of  the  square  base.    Call  this  length,  s.    The  height  is  three  times  as  big,  so  it  is  3s.    The  total  volume  is  then  3s3=3000.    So  s3=1000  or  s=10.    The  width  of  the  box  is  then  10.    (b)  Algebra  10,  13,  Geometry  4  

4. The  area  of  a  triangle  is  81  inches  squared.  Its  base  is  half  its  height.    What  is  the  height  of  the  triangle?  Call  the  base  of  the  triangle  b  and  the  height  h.    Then  the  area  of  the  triangle  is  (1/2)bh.    But  b=(1/2)h.    So  the  area  is  (1/2)(1/2)hh  by  substitution  for  b.    Also,  the  area  is  given  to  be  81.    Hence  81=(1/4)h2.    That  is,  h2=4*81.    So  h=18.  (d)  Algebra  10,  13,  Geometry  2  

5. Suppose  that  the  number  of  cells  in  a  petri  dish  is  600  one  hour  after  the  cells  are  plated  into  the  dish.    Three  hours  after  being  plated  the  cell  population  has  grown  to  3000.    If  the  population  of  cells  in  the  petri  dish  is  growing  exponentially,  what  is  the  number  of  cells  in  the  dish  7  hours  after  they  were  plated?  The  general  formula  for  an  exponential  function  is  P(t)=Cat,  where  P  is  the  size  of  the  function  at  time  t,  C  is  the  size  of  the  function  at  time  0,  and  a  is  some  value  greater  than  0.    We  know  that  600=Ca  and  3000=Ca3.    Dividing  the  last  equation  by  the  previous,  we  find  that  a2=3000/600  =  5.    Therefore,  P(7)=Ca7=Ca3(a2)2=3000(5)2=3000(25)=75,000.  (d)  Algebra  9,  Pre-­‐calculus  1,2  

6. A  function  is  said  to  have  period  B  if  f(x+B)=f(x)  for  all  values  of  x,  and  B  is  the  smallest  such  positive  number.    What  is  the  period  of  the  graph  shown  below?    

 Examining  the  graph  shows  that  it  repeats  a  full  cycle  every  0.4π.  (b)  Trigonometry  1  

7. The  inequality  0 < 3𝑥 + 2 < 𝑑  is  equivalent  to    0 ≠ 3𝑥 + 2  and   3𝑥 + 2 < 𝑑,    which  is  equivalent  to  𝑥 ≠ !!

!  and  −𝑑 < 3𝑥 + 2 < 𝑑,  which  is  equivalent  to  

𝑥 ≠ !!!  and  –𝑑 − 2 < 3𝑥 < 𝑑 − 2,  which  is  equivalent  to  

𝑥 ≠ !!!  and  –!!!

!< 𝑥 < !!!

!.    (d)  Algebra  7  

 8. Find  interval(s)  on  which  5x2-­‐9x+2  >0.  

The  function  5x2-­‐9x+2  is  an  upward  facing  parabola,  so  it  will  only  be  less  than  or  equal  to  0  between  its  zeros.    For  other  x-­‐values  the  function  will  be  greater  than  0.    To  find  these  zeros,  we  can  use  the  quadratic  formula:      𝑥 = !± !!!!×!×!

!×!= !± !"!!"

!"= !± !"

!".  (d)  Algebra  6,  11  

9. Find  the  distance  between  points  P  and  Q  in  the  following  figure.  

 

-1.5π -π -0.5π 0 0.5π π 1.5π

-3

-2

-1

1

2

3

-1 0 1 2 3 4 5 6

1

2

3

4

P

Q

We  can  think  of  this  as  the  distance  formula  or  as  the  Pythagorean  Theorem.    The  distance  between  P  and  Q= (5− 2)! + (4− 2)! = 9+ 4 = 13.  (d)  Algebra  8  

10. At  which  value  of  of  θ,  0 ≤ θ ≤ !!  ,  does  csc(θ)  =  2?    

Because  csc(θ)=1/  sin(θ),  this  is  the  same  question  as:      For  what  value  of    θ,  0 ≤ θ ≤ !

!  ,  does  sin(θ)  =  ½?    The  answer  is  !

!.  (b)  Trigonometry  2,  4  

11. If  log3(2x+5)=4,  then  x=  2x+5=34=81,  so  2x=81-­‐5=76.    Hence,  x=76/2  =  38.  (d)  Algebra  1,  Pre-­‐calculus  4,5  

12. Let  𝑔 𝑡 = 2𝑡 − 3.    Find  ! !!! !!(!)!

.    Choose  the  most  reduced  answer.  ! !!! !!(!)

!= ! !!! !!! !!!!

!= !!!!!!! !!!!

!= !!!!! !!!!

!  .  (d)  Algebra  11,  

12  13. A  function,  f,    is  increasing  on  an  interval  (a,b)  if  for  x,y  in  (a,b)  with  x<y,  

f(x)<f(y).    Determine  the  x-­‐interval(s)  on  which  the  pictured  graph  is  increasing.

 (-­‐2,2)  (b)  

   

-6 -4 -2 0 2 4 6

-2

2

 14. Which  of  the  following  best  represents  the  graph  of  𝑦 = 2− 𝑒!!!?  

(a)  Algebra  12,  Pre-­‐calulus  6,  7  

15. A  cylinder  in  which  the  radius  equals  the  height  contains  one  largest  possible  sphere.    How  much  volume  is  inside  of  the  cylinder,  but  outside  of  the  sphere?    Because  r=h,  give  your  answer  in  terms  of  r.  

      The  volume  of  a  cylinder  is  𝜋𝑟!ℎ,  but  because  r=h,  the  volume  of  this  cylinder  is  𝜋𝑟!.    The  volume  of  the  sphere  is  (4/3)πR3,  where  R  is  the  radius  of  the  sphere.    Because  the  sphere  is  the  largest  one  that  fits  into  the  given  cylinder,  we  know  its  diameter  to  equal  r,  so  R=r/2.    Therefore,  the  volume  of  the  sphere  is  (4/3)π(r/2)3=(4/3)πr3/8=πr3/6.    The  volume  of  the  cylinder  outside  of  the  sphere  is  then  𝜋𝑟!-­‐  πr3/6  =  5πr3/6.  (d)  Geometry  4,5  

-5 -4 -3 -2 -1 0 1 2 3 4 5

-3

-2

-1

1

2

3