3.匀速和匀变速转动 匀速转动a de =09=90+Ot dt 匀变速转动a d cont dt O=0+at 9=00+0t+-an2= = 0 dt d 匀速转动  2 0 0 0 2 1 t t t cont t          = + + = + = = d d 匀变速转动 3.匀速和匀变速转动  = +t 0