u >C No meaning. Max imum Speed is C procedure to solve the problem D)establish coordinate 2)determine the moving frame and rest frame 3)u is the positive speed of s to S 4) use formula to get relation among△x,△t,△x △ t and solve problen S↑S Pu > c No meaning. Maximum Speed is C 4.procedure to solve the problem 1)establish coordinate 2)determine the moving frame and rest frame 3)u is the positive speed of S’ to S 4)use formula to get relation among x,  t,  x ’  t’ and solve problem P o  S u x  o x S