Hello
I need to plot this simple system:
x'' = -x
using midpoint Euler.
u1 = -x , u2 = -x'
u1' = u2
u2' = -x
u1(n+1) = u1(n) + h*?
u2(n+1) = u2(n) + h*f((1/2)*(u1(n) + u1(n+1))
We don't know u1(n+1). I tried approximating it with u1(n+1) = u1(n) + h*u2(n)
u2(1+i) =...