What should I write? GDC

[yghydumdam]

Hello, I've got a question concerning paper 2. The point is that I don't know what I am actually supposed to write while using GDC.

1. whenever I use GDC and write the outcome (or graph or whatever) in the paper, am I supposed to write something like "from GDC" or is it unnecessary? My teacher always told us to write it but I didn't notice any similar comments in marks schemes.

2. One thing is that I don't want to waste time but the other - I don't know what is the minimum I should write to achieve a point, for instance:

let there be a binomial distribution X~Bin(7,0.25)
when I am supposed to find P(X=<2), should I elaborate that this is equal to P(X=0)+P(X=1)+P(X=2) and next, it is equal to: 7C0*(1/4)^0*(3/4)^7 + 7C1... et cetera... and then finally, the outcome from GDC

what do you think is enough to get a point?

[TogoPogo]

It's always good to show that you use your GDC when solving questions; our teacher told us that if we're showing the zeroes to a function or showing that a function is increasing/decreasing on a certain domain, then we should roughly sketch a small graph for proof. She didn't tell us to state "GDC" but I don't think it would hurt.

As for the binomial distribution, our teacher said that P(X<=2)=binomcdf(n,p,2)= blahblah is enough for working and that it's not necessary to list out all the discrete values for X (as you have).

[Miralda]

No score for the term "using calculator"

you should

1) Copy the graph of a function when GDC was used

2) Write down the formula for Bin Distr or Cum Bin Distribution and just copy the number you got

3) For normal distribution: draw the bell-shaped curve and shade the region

4) For matrices- just copy the result from the screen

GDC notation normally will not give you marks.