Recent content by Karla

Thanks very much guys :)

Sorry, cryptic probably means i don't understand them, For the angle between 2 vectors in the past i have used, Cos Theta = (AxBx + AyBy) / |a|*|b| then I simply did Cos-1(Theta) I attempted to alter this formula to work with 3d vectors, but it went very wrong. Thanks for any help, i do...

Any none cryptic ways for working this out? How can the dot product be used? I know a formula for 2d angle calculating but i can't find any info for 3d? And what is R^2 exactly?

Hi, If you have 2 3d vectors a and b, i.e (1,2,3) and (3,4,5) how would you calculate the angle between them? Thanks for any advice, Karla

Hi all, Im doing some work with the triangular numbers, pretty basic stuff: 1 3 6 10 15 Now I am trying to understand how to get the formula for calculating the nth term +1, the formula is: n(n+1)/2 I have tried doing a difference table, only to find that the second difference is...