Subscriber comments


  • 9 May Oliver Bowles
    HL Mock Paper 1B
    Thank you Simon for the feedback - paper & markscheme now updated above.
  • 6 May Simon Halliday
    HL Mock Paper 1B
    For question 11a there seems to be an issue. The mark scheme seems to have x component of one of the vectors as zero when calculating the scalar product. Why would this be the case?
  • 6 May Simon Halliday
    HL Mock Paper 1B SOLUTIONS
    Is there an error with Q11a. The scalar product in the numerator of line 1 in the mark scheme seems to be incomplete?
  • 6 May Yolanda Zhang
    SL Arithmetic Sequences
    Thanks! It works now.
  • 5 May Taren Ikea
    SL Exam Practice - Paper 1
    Q6 b) I think that 32 is indicated as the answer in the markscheme. It is just not highlighted. See if you can find the solution right below the bolded 38.0617...
  • 5 May Taren Ikea
    SL Exam Practice - Paper 1
    I believe it is because the 2kg quantity of Indium tin oxide is rounded to the nearest 0.01 kg. This means that the exact quantity of Indium is between 2.005 (upper bound) and 1.995 (lower bound). We find the upper and lower bound by adding...
  • 5 May Jim Noble
    SL Arithmetic Sequences
    Try now....
  • 5 May Yolanda Zhang
    SL Arithmetic Sequences
    The 'solutions' for the exam-style questions require an access code/key.
  • 3 May Catarina Ribeiro
    SL Exam Practice - Paper 1
    Hi, Oliver. thank you for your work on producing this assessment. I have some questions: In Q5 b) you have in the table th evariables c and d for velocity in miles per hour and miles per second, since changing the units changes the values,...
  • 29 Apr Niomi Anderson
    HL Mock Paper 2B SOLUTIONS
    Yes. That is correct. Can someone confirm that in Q5b the shortest distance between odd vertices is in fact 300 (E-C-B, A-G)?
  • 28 Apr Andre Escobar
    SL Exam Practice - Paper 1
    Hi, Q1 in part b i & ii, why do they add and subtract 5 to the maximum quantity? 2.005 & 1.995
  • 28 Apr MaryAnn Cayabyab
    HL Mock Paper 2B SOLUTIONS
    Can someone confirm with me that Question #1 b ii, should be V=(1.2)x(-1.875x+1.5) rather than V=(1.5)x(-1.875x+1.5)? Interestingly enough working through dv/dx and finding the optimal value results in the same values for x and h.