BRIEF QUIZ ANSWERS FOR PRECALCULUS STUDENTS
In this document you will find brief answers to quiz questions.
If the quiz question is a homework problem, and the answer
is in the back of the book, then the brief answer that you
will see below will be only ``See the back of the book.''
Week 1
Week 2
- See the back of the book.
- See the back of the book.
- See the back of the book.
Week 3
- This graph looks like the y=x^2 curve when x is between
-1 and +1. Everywhere else it is constant at height 1.
- See the back of the book.
- The final function is -2*[(((-x)+1)+1)^2 +2] = -2*x^2+8*x-12.
Week 4
- See the back of the book.
- There are three parts to the answer.
- D(p) = 27000 + 3000*(10-p) = -3000*p + 57000.
- R(p) = p*D(p) = -3000*p^2 + 57000*p.
- Since R(p) = -3000*(p - 19/2)^2 + 3000*(19/2)^2,
the price which maximizes revenue is 19/2 = 9.5 dollars.
Week 5
Week 6
- If f is even and g is odd, then f o g is even.
To see this, note that f o g(-x) = f(g(-x)) = f(-g(x)) = f(g(x)) =
f o g(x).
- See the back of the book.
Week 7
- To find the inverse interchange x and y and solve for y.
- f^(-1)(x) = 1/(1-x)
- f^(-1)(x) = cube_root(1-x^3)
- The only rational root is -1. (In fact, this is the
only real root.)
- P(-2) = -12.
Week 8
- This simplifies to 2*square_root(6)*i
- See the back of the book.
- P(i) = -2-2*i
- Vertical asymptotes are: x=3, x=-2. Horizontal
asymptote is: y=1.
Week 9
- T or F
- False, they are not equal.
For example, when a=2=c and b=1 you get
4 on the left hand side and 2 on the right hand side.
- True: log_a(1) = 0 for any base a.
- False, log_10(2) and log_10(5) are both positive
since 2, 5 and 10 are all greater than 1.
- See the back of the book.
- See the back of the book.
Week 10
Spring Break
Week 11
Test 2.
Week 12
Week 13
Week 14
Week 15
Last modified on Feb 5, 1998.