Corrections to IA Maths for Natural Sciences Tripos Answers


This document last updated 12 May 2012.

I'll list corrections to the main pdf documents here and incorporate them into the main pdf documents from time to time.

2002 II 1 while true, my answer isn't helpful: the equation seems to describe points on a curve in 3D space, but it's not obvious how to express the curve simply. I tried assuming (without loss of generality) that the vector a is along the x-axis and the vector c is in the xy-plane. One can then solve for the vector r=(x,y,z) in terms of lambda. But it still isn't obvious what the curve is.

2002 II 7 (a) should be y = A(exp(-2x) - (2/3)exp(-3x)) + exp(-3x) + x - 5/6

2002 II 9 (ii) should be 1 + 2x + 2x^2

2003 I 4 in the first part the second term should be -(2/3)x^3, not x^3, and (ii) should be ln(ln(x)) + c

2005 I 9 (b) should be y=e^(-x)[1/alpha + c(x^(-alpha))] and y=e^(-x)[ln(x) + c] when alpha is zero

2008 II 19 (b) They've confusingly used Sigma(x) to mean a function of x and not a sum, and Sigma0 is just some constant...: f(x) = Acos(kx) + Bsin(kx) where A, B are constants; V(x,y) = -(pi)(Sigma0)cos(x)exp(-|y|)


Ian Rudy (graphic containing email address for iar1)