Math 150 – Fall 2015: Quiz 8 – Section 5D, 6A, 6B, and 7A
Group Worksheet (5 pts):
Yes or No Section Number(5 pts):
(circle yes if this is the worksheet your group would like to be graded)
If this is NOT the group worksheet, print your name here:
(-10 pts if you don’t turn in an individual worksheet with your name in this blank)
For BOTH group and individual worksheets, print the names of all members of the group who attended lab
and contributed to the worksheet here (10 pts):
Directions: You may not use your class notes, book, calculator, cell phone, any electronic devices, etc.
Your grade will be determined by your final answer and the work to justify it. You must show all your work
to receive credit. Your group should turn in one group worksheet, and each individual should turn in their
own worksheet. Only the group worksheet will count as part of your grade.
1. (11 pts) Solve the equation ln 3 + ln(2x + 9) = 2 ln x.
2. (11 pts) Solve the equation 5e2x + 13ex − 6 = 0.
3. (11 pts) Answer the following questions for the function f (x) = −3 log2 (x + 3) + 4.
Domain:
Range:
x-intercept:
y-intercept:
Is the function increasing or decreasing?
4. (11 pts) If ln 2 = a, ln 3 = b, ln 5 = c, and ln 11 = d, evaluate and fully simplify log11
25
36
.
5. (11 pts) Fully simplify 2 log10 6 − 2 log10 15 − 4 log10 2.
6. (11 pts) What is the half-life of a sample that decayed 39% after 4 years? Include the units in your
answer.
7. (11 pts) Suppose that a population of mice with initial population P triples every 20 days. What is
the exponential growth model where t is time in days?
8. (11 pts) How many mL of 30% saline and how many mL of 55% saline should be mixed to get 100 mL
of a 40% saline solution? Include the units in your answer.