(Original post by CharleeB)
I dont know about edexcel, but the practise papers for MEI are very unhelpful. At AS i was only given them to revise from and when I got in the real exam I found the structure very different and that I was underprepared, so now I treat them with caution. Real papers are a much better resource.
yeh well doing every past paper i could lay my hands on for c3 did f*** all so i expect its all a waste of time anyway. *pessimistic*
(Original post by kdv)
7a) yes because its losing mass, and i think k has to be above 0 so that the equation stays a minus
7b)differentiate the equation they give you using 'a(to the x) lna' and your equation frm part a) should look familiar with M=10(0.98)^t and -k=ln(0.98)
5d) is a proof expanding the parametric for y and then substituting in x. 5e) however, is a mystery to me too! (only one mark really)
hope that helps
I still don't understand 7b, though. Would somebody mind working it through??
Or - can anyone explain 5e??
- please, please, please??