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This list of frequently asked questions. The list consists of questions that were asked most frequently. Please look for answers in this list first before asking the same question again. Thank you!


Q1 How many hours do I need to spend on the course?
A1 The planned study load is about 6 to 8 hours a week.

Q2 Do I need to watch the lectures live in the corresponding week?
A2 No, you can watch the lectures during the course whenever you like.

Q3 Can I contact the instructor or teaching assistants?
A3 Not directly. The discussion forum is the appropriate venue for questions. Instructors monitor the discussion forum and try to respond to the most important questions; in many cases response from other students and peers will be both adequate and faster.

Q4 Can I still finish all assignments when I start later in the course?
A4 Yes you can. There is one deadline for all the exercises on September 29, 23.30.

Technical issues & Entering answers

Q1 My answer is not accepted and I got the message: "invalid input: could not parse..."
A1 Please check the following:

  • Did you write "*" for every multiplication?
  • Are all brackets right?
  • In case you are using an international keyboard on a Mac: if you type "^", you first get a small version of that symbol. If you hit the space key, it becomes larger. Make sure that your formula contains the larger version, otherwise it cannot be parsed.

Q2 The answer is a square root. How can I use a square root in my answer?
A2 You can enter "sqrt(x)", to enter the square root of x. Be sure to check out the "Entering Mathematical Expressions" in "Getting Started" and explore edX's documentation on entering mathematical expressions.

Q3 The drag and drop exercises do not work on my tablet.
A3 This is unfortunately true, the drag and drop exercises are not accesible on touch screen devices.

Q4 Which browser can I use when working on this edX course?
A4 We advise you to use Chrome, Firefox or Safari. Internet Explorer is not supported by edX, so please use one of the advised browsers instead.

Q5 How do I know if I should give an exact or numerical answer?
A5 We always expect an exact answer, so sqrt(3)/pi instead of 0.5513. If we expect a numerical answer it is stated explicitly in the questions.

Q6 Why can't I check my answer?
A6 There have been several reports of questions where the "Check"-button does not appear after an answer has been selected or entered. This seems to be a technical glitch and we are looking into it.
A quick solution is the following: hit the "Save"-button after you selected an answer, and the "Check"-button will appear.

Verified Certificate

Q1 When do I get my verified certificate?
A1 As soon as the course is finished and you scored 60% or higher, you'll be able to download your certificate in the week after the course ends. After that, you can download your certificate directly from the Progress Tab, or from your Student Dashboard (look for the Download button next to the name of our course).

For more information on how to generate and download your certificates, explore edX's documentation on how to generate your certificate.