ahh i c...but i always find difficulty on the D.E( differential equation) because i don't have enough ree. / books.. actually a I am a poor students w/c don't have enough knowledge about thid topic. BSED-math is my course but unfortunately my subject in D.E is modular( self study). we don't have a class session, they only given us an assignment. that's why i always encountered some difficulty in this topic.