Example d西 d =Ay-By2,AB>0,0)=0 Solution A y- B+(分-B)eA 生0 vftl-0 0 -0 牛0 (e).t-0,B-0 (64<0,B<0 0a0Example dy dt = Ay−By2 ,AB > 0, y(0) = y0 Solution y = A B+ ( A y0 −B)e−At t y 0 A B y2 (t)= A B y1(t)=0 dy dt <0 dy dt <0 dy dt >0 (a ) A>0, B>0 (c) t y y2 (t)= A B y1(t)=0 dy dt >0 dy dt <0 dy dt >0 (b) A<0, B<0 0 A B (d)