If the condition/parameter is rapidity of 1 hyperbolic radian, what is the proper velocity w dx/dτ in units of c?
CREATE TABLE "table1_15314901_1" (
  "condition_parameter" text,
  "coordinate_velocity_v_dx_dt_in_units_of_c" text,
  "velocity_angle_in_i_radians" text,
  "proper_velocity_w_dx_d_in_units_of_c" text,
  "lorentz_factor_dt_d_e_mc_2" text
);
SELECT "proper_velocity_w_dx_d_in_units_of_c" FROM "table1_15314901_1" WHERE "condition_parameter"='Rapidity of 1 hyperbolic radian';