Author Archives: avner segal

Common Mistakes in Quiz 2


The quizzes should be in the MLC by Thursday morning, I will post here when they get there. There were a few common mistakes you should take under consideration when preparing to the midterm:

  • Question 1: Many tried to solve the equation instead of using IVT and some did use IVT while forgetting to state the function is continuous.
  • Question 2: Many got the derivative of e^(x^4) wrong. See that you know how to do it!
  • Quesiton 4: Many of you don’t remember the definition of the derivative, this will almost certainly appear in the midterm and it is a relatively easy problem once you write down the definition.

Good luck!

Quiz 1 Solutions

Quiz 1 Column A

Quiz 1 Column B

Quiz 1 Column C

A few common mistakes that I suggest you reflect upon before the midterm next week:

  • In the problem with compounded interest, many of you were confused regarding the values of n and t. I remind you that n is the number of compounds per year (that is, for a quarterly compund n=4, for monthly compund n=12 and for a daily one n=365) and t is the span of the loan measured in years (so half a year will give t=1/2, two years will give t=2 and one month is t=1/12).
  • Many of you had trouble with finding the slope of the demand function see that you know how to write the equations and solve them; if not: come to office hours!
  • Many managed to write the correct demand formula in terms of q=ap+b but failed to invert the equation to be and write it as p=cq+d. Once again, if you are unsure how to do this: come to office hours!

Quizzes, Teaching Replacement, Office Hours Cancellations


  1. Quizzes are in the MLC, in order to pick them up you need to bring your UBCcard. There were two unrecognizable quizzes so if you can’t find yours in the MLC plelas contact me on Wednsday after class.
  2. I remind you that in the following dates I won’t come to class and another instructor will replace me:
    • October 3rd
    • October 12th
    • October 17th
    • October 24th
  3. I won’t hold office hours on October 4th and please check the website before coming to office hours throughout October as I might need to cancel other office hours.
  4. On Friday we will have our second quiz. Please remember to bring your UBCcard with you so you can fill out your student numbers. Also, I remind you no calculators or any other electronic devices are allowed. You may only use your “cheat sheets”.

Shana Tove (“Happy new year” in Hebrew)

Quiz 1 Practice

Here is an exemplary quiz. The material for quiz 1 covers everything up to and including (two sided) limits. Later this week I will upload a solution for this quiz.

Pleas find some quit time (about 15-20 minutes) and try to solve it (preferably without looking at it before that).

A short explanation about the structure:

  • There are two “Very short answer questions” – For these you are supposed to supply only the final answer.
  • Ther are two “Short answer questions” – Here you are supposed to supply a final answer with a short explanation of how you got it.
  • There is one “Long answer question” – This question is multiparted and you should supply a final answer together with an explanation of how you got it.

Please remember: Calculator-ready solutions only!

In fact, you are not supposed to use calculators in the quiz.

Exemplary Quiz

The different kinds of interest rates and plans


After talking with a student I figured that the quick overview I had on Monday might caused a little confusion regarding effective interest, effective interest rate and simple interest (it even confused me for a couple of minutes). So inorder to avoid further confusion, here is a summary of what you should know, hopefully it will help.

Kinds of Interest Rates

There are 3 kinds of interest rates:

  • j – effective interest rate
  • i – nominal interest rate
  • r – real interest rate

Kinds of Interest Programs

There are 4 kinds of interest programs:

  • Simple interest: FV=PV*(1+jt)
  • Effective interest: FV=PV*(1+j)^t
  • Compounded Interest: FV=PV*(1+i/n)^nt
  • Continuously Compounded Interest: FV=PV*e^rt

We noted that effective interest is the same as compounded interest when it is compounded yearly, however (and here begins the confusing part) it is computed using the effective interest rate. Now, the simple interest plan also uses the effective interest rate (which is the second cause for confusion) but it is compounded once in the whole loan period and not yearly.