由 uncry1 於 星期六 二月 11, 2006 12:39 am
#ed_op#DIV#ed_cl#Try y'=p => y'' = dp/dx = dp/dy * dy/dx = dp/dy * p =pp'#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl# #ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#ypp' = 2p^2 => p' = (2p)/ y 分離變量得 p= Cy^2 , C is constant#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl# #ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#y'= Cy^2 再一次得 - 1/y = Cx + K , K is constant#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl# #ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#y= (cx+k)^-1 where c = -C , k= -K#ed_op#/DIV#ed_cl#