I have some problems about Operational Amplifiers from the communication option. I have had three mental breakdowns in class now.. Why do we need an inverting and a non-inverting amplifier. Its name suggest the concept of amplifying signals, then WHY would we want an inverting one? I mean, it doesn't help by inverting the signal sent. It's like playing a song backwards. It just doesn't make sense!
I know all the theory of drawing it and calculating gain and stuff, but why do we have them?
What use do they have?
- Camilla

Say you are doing an IB maths paper and you are on a question that will reward you 5 marks for a worked answer. There is the easy way of doing it with your calculator or the hard way of working it out yourself (which you suspect is the way they want you to work it out), you can only remember the way to do it on the calculator so do you:
a) Write down some of the sums you used or
b) write down everything you pressed on the calculator in the hope you will get some of the marks?
- Holly

IB Math SL Paper 2:
In the expansion of (2-ax)^5 the coefficient of x^2 is 5. Find the value of a.
I tried is using the formula for finding any specific term but I didn't get far.
- Kimberly

This questions has a Video Answer

I was wondering how you can find a good and useful way of interpreting novels and interpreting the symbolism! I mean, I've read through York notes but I have come to the firm conclusion that they are making it up as they go along! For example, you could get a passage where a couple are having a romantic conversation and drinking tea in the garden, and suddenly the tea symbolises the struggles that workers hundreds of years ago had to endure in the tea plantations and the hardships that they went through, and thus the tea symbolises injustice and moral corruption which makes the reader feel a sense of resentment towards the couple. I mean come on. I was admiring the guy's improvisation to impress the girl, not the tea. So, was wondering what the TRUE method and key is to obtain the wisdom to interpret texts?
- Alexander