Math's Lesson

i owe someone a thanks.
He spared me his invaluableners time to teach us modern maths, i did learnt and get improved a lot, he able to express well and we able to comprehensive as well also, i'll have my july paper text on next week, only left 2days more to pick up all the formula that i was forgotten on my pretty secondary schools life!

I feel slightly easier if compare to previously('non-stop talking when teacher teaching'), at least i can understand and master some of it right now.

Let me recall some of your memory,
sin = o/h tan = o/a cos = a/h
or often remembered by: soh toa cah

Spheres Volume?
Cylindar Volume?

Universal set?
Subset/Interset?

lol, sounds familiar kah?
Wish me luck!!


p/s:Thanks to thoo's brother which is amazed+terrible strong in maths!