2 {\displaystyle {\sqrt {2}}}
a ´ + 5 {\displaystyle {\acute {a}}+{\sqrt {5}}}
a = γ ˙ u + γ u ˙ {\displaystyle \mathbf {a} ={\dot {\gamma }}\mathbf {u} +\gamma \mathbf {\dot {u}} }
