time series

it was such a long time since i blog about my studies.
(or i never blog about my studies??)
and now, i CANNOT TAHAN liao..
i dont know how many piece of paper i wasted doing that tutorial (ony 3 questions)
substitute this subtitute that...
after a few pages of working
come out with the formulas
plug in the figures
count a few times
and YET i couldnt get the answer!!!
seriously worry,
what if this kind of situation happen during tests or exam???


ginael kee, concentrate and don't so careless ok? please!