Jump to content


  • Content Count

  • Joined

  • Last visited

Community Reputation

2 Unknown

Profile Information

  • Gender
  • Exams
    Nov 2011
  • Country

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. From Wikipedia (http://en.wikipedia.org/wiki/Voltage_divider): Applying Ohm's Law, the relationship between the input voltage, Vin, and the output voltage, Vout, can be found: Proof: If we have a circuit such as: http://en.wikipedia.org/wiki/File:Impedance_Voltage_divider.png Vin = I*(Z1+Z2) and Vout = I*Z2 Thus, I = Vin/(Z1+Z2) Finally, Vout=Vin*Z2/(Z1+Z2)
  2. One standard deviation above the mean - 2.73+1.34 = 4.07 Therefore, the number of bedrooms must be greater than 4.07. Thus, the number of bedrooms must be either 5 or 6 (as these are the only two options with number of bedrooms greater than 4.07) There are 15 houses with 5 bedrooms. There are 8 houses with 6 bedrooms. Add these together 15+8=23 Thus, there are 23 houses with either 5 or 6 bedrooms. 23 houses with number of bedrooms greater than 4.07 23 houses with number of bedrooms greater than one standard deviation above the mean.
  3. First series: This is not a series. Sinx is a function, thus there is no one answer to the series 1 + sinx + sin2x + sin3x Second: Desy Glau proved this above. Third: Using double angle formula: sin(2k+1x) = sin(2*2kx) As sin2a=2sina*cosa for any a (real number) If a = 2kx Then sin(2*2kx)=2sin(2kx)*cos(2kx))
  4. Basically, these two pieces seem quite different, but once you go through them each in detail you start to notice similarities. I'm not going to give you any specific answers, mainly because I haven't finished finding comparisons between the two works either. How would you go about comparing them? Well for each of the headings write out the features of each of the two set works separately, then look for similarities and differences between the two. You may need to do this in quite a bit of depth (studying the scores really helps), before you can find any similarities. A good idea is to focus
  5. My teacher seems to think that this essay in Q4 should be pretty similar to those you write in paper 2. That is, always add as many facts as you can, economic figures are good, but you can also add in years, names of specific treaties/people/countries influential in the topic, any other sort of data (social - eg. amount of protests, political - eg. number of governments in a particular time period etc.). There are heaps of ways of adding your own knowledge into the essay. Also, don't forget to give at least on point for all 5 sources, otherwise the maximum mark you can get is 5/8. It should
  6. It is probably a bit late to start the HL course with only one year to go, especially if you are learning it yourself, but good luck anyway!
  7. Integrals look right to me, and I checked them with calculator. However, for both questions it is a question about whether the algebraic area or the geometrical area is to be found, as both questions have functions which cross the x-axis within the intervals. Edit: Pretty sure you would be looking for the geometric area, in which case you would have to take the two integrals (one with limits 0 and pi/4 and one with limits pi/4, 3pi/4) and add the absolute value of both of these integrals together
  8. Yes, SL physics needs to know what angular velocity is. It took me awhile to work it out, and its name is confusing. Basically velocity is the change in something per time unit (second), thus angular velocity is the change in the angle per time unit (second). Its units are rads s-1. Angular velocity is NOT the same as angular frequency. Angular frequency is the same as angular speed, that is to say, both angular frequency and angular speed are a scalar quantity of the magnitude of angular velocity (a vector quantity). The differences between angular velocity and angular frequency/speed are th
  9. Answer is D Always remember in circular motion: speed may be constant, but velocity is changing! As velocity is a scalar product, measure in direction and magnitude. The direction is always changing (the direction at some point is the tangent of its path at that point), thus the velocity is changing. This also leads into the idea that there is a force being applied upon the satellite (as there is change in velocity, meaning there is acceleration, and thus there is a force). This is called the centripetal (not centrifugal) force. Thus, its great to know that the connection between velocity and
  10. Two things. You might want to be a bit careful with how much context you give in your first paragraph as it is unnecessary and adds to the word count. Secondly You may way to be a bit more clear with the method. I am using dot points to clearly show the structure of my essay (one dot point for one major focus/body paragraph of my essay.
  11. Noone seems to have mentioned historiography which is necessary for a seven (possibly six) in paper two. So if you want to get a good mark you need to include historiography as well as facts and specific details. Historian's names are great to add or the type they were (eg. Revisionist historians) but the easiest (and most basic) way would just to contrast two opposing views on whatever you are writing about.
  12. I agree with the Eccentric Pianist, books are really helpful. I find getting something at a medium level that you can understand mostly without a dictionary, and work out words you don't know from the context around them. It really helps to expose you to new vocab but also familiarise with grammar and sentence construction. I have found it really good to read the book out aloud, as that helps pronunciation (and also seems to imprint grammar better in my mind) but this may be a bit late for you if you have already finished the oral component. Basically, I know you don't want to hear this, but a
  13. She used mathematical induction to prove the above equation, that is, essentially she proved for all n (despite not showing that n=2,3 is true). If her proof is confusing, you NEED to go over mathematical induction (or learn it if you haven't already), ask your maths teacher about it, as it can be a little confusing to grasp the logic behind this type of proof. I am assuming you are doing the HL maths course, in which case you will need to know this method of proof. I am not sure whether SL students need to know this. If you want to verify for n=2 and n=3 (despite Desy Glau proves for all n)
  14. I know that my brother got a 5 two years ago. I am aiming for a 7, I try to do as much study as I can, essentially doing all the questions I can from the textbook and past papers. That being said, my brother didn't do too much study and still got a 5, although he had a tutor for one hour a week, and I don't, I think that really improved his grade, so consider getting one if you want to improve your mark. Although his tutor was really good, I don't know if an average tutor would be able to teach everything in the HL course well, considering its difficulties.
  • Create New...