Key to The Practice Final

Problem 1

A.  20        B.  -1        C.  7        D.  16        E.  3

Problem 2

(infinity,-1] u [4,infinity)

Problem 3

- x(x - 3) / [3x(x - 2)]

Problem 4

1/9 (x + 2)(x - 3)(x - 6)

Problem 6

A.  (9/10, 121/20)

B.  (0,2)

C.  (2,0), (-1/5,0)

Problem 7

A.  2 or 0 positive roots, 1 negative root

B.  The only possible rational roots are 1,3,9,-1,-3,-9

C.  Roots:  3, sqrt(3), -sqrt(3)        y = (x - sqrt3)(x + sqrt3)(x - 3)

Problem 8

A.  y = -2/3 x - 17/3

B.  (-1.2, 2.1)

C.  The only possible rational roots are 1 and -1.  Using synthetic division, we see that the remainder is not zero for either.  Hence the endpoints are not rational.