Like that, you see if you see that you will see there is an L square V L cube V these two remain same, L cube V L 4, there is an you know increase of whatever this into L this remain same, another L in a L cube L 4 L 4 L 5, it is actually easy to work it out you can if you, I mean go to that you will find it is quite easy. Now, x c dash will become x c by L, U 1 is basically dash is u 1 by V, which is equal to 1, because you see V is actually the forward speed with a small change, basically u 1 will be V, u 1 equal to V cos beta or cos of heading angle, but the heading angle is taken as small side becomes equal to 1.