What is the coordinate velocity v dx/dt in units of c total number if the velocity angle η in i-radians is ln[2 + √5] ≅ 1.444?
create table table_15314901_1 (coordinate_velocity_v_dx_dt_in_units_of_c varchar, velocity_angle_η_in_i_radians varchar, PRIMARY KEY (coordinate_velocity_v_dx_dt_in_units_of_c))
select count(coordinate_velocity_v_dx_dt_in_units_of_c) from table_15314901_1 where velocity_angle_η_in_i_radians = "ln[2 + √5] ≅ 1.444"