continous triangle-triangle intersection test

[backtobedlam]

I have two triangles in the sence,one is movable,the other is not.The position of the three points of the movable triangle between two continous moment are known,now I want to know if the two triangle intersected between the two moments,if intersected,when is the time they begun to intersect?

[backtobedlam]

forgot to mention,all the points move linearly。