Originally Posted by
Madspeter I've come this far:
an = 4an-1 + 5an-2
a1 = 2
a2 = 6
roots
x1 = 5
x2 = -1
I insert roots in : an = U*s1^n + V*s2^n Correct, except that you mean x1 and x2 - see below
which gives : an = 4*5^n + 5*(-1)^n No
what now?
an could e.g. be a1?