No announcement yet.

Question about infinite series

  • Filter
  • Time
  • Show
Clear All
new posts

  • Question about infinite series

    hi, all... i've encountered this problem when i was doing the May 2001 P exam, and i think it's about sum of infinite series, but i do not know how they got the solution/simplification...
    they first have
    500 = 8 + 8*1.07 + 8*(1.07^2) +... + 8*(1.07 ^(m-1) )

    then they have the right side equal to(simplified to)
    8*{ [1 - (1.07^m)] /[1-1.07]}

    could anyone tell me what rule did they follow when they did the simplification??

    thank you very much!

  • #2
    i also noticed that the exams from those years (2000-2003) had a lot of questions related to calculus, they do not involve probability at all (for example, asking for the slope of the tangent line at a point on a curve).

    i know the P Exam right now deleted some calculus parts comparing to 2000-2003 exams, but could anyone tell me if i should still expect to see those types of calculus-oriented problems??

    thank you guys very much!!


    • #3
      They used the formula for the sum of a geometric series. This formula will be your best friend come exam FM/2. In terms of that exam they are looking to find the number of payments m of size 8 needed to accumulate 500 at 7% compound interest.

      Calculus is no longer tested directly on any of the exams, i.e., any problem where calculus needs to be used should be in relation to the syllabus material.