Answer: V = 299,958589.8 m/s
Explanation: To calculate Rigel velocity relative to us, we should use doppler effect formula.
Fo = (c + Vo) f/ ( c - Vs)
Fo/f = (c + Vo) / ( c - Vs)
If Vo = Vs = V approximately
4.26 × 10^10 = (3×10^8 + V) 6.17×10^14/(3×10^8 - V)
4.26×10^10/6.17×10^14 = (3×10^8 + V)/(3×10^8 - V)
6.9×10^-5 = (3×10^8 + V)/(3×10^8 - V)
Cross multiply
20713.13 - 6.9×10^-5V = 3×10^8 + V
Collect the like terms
6.9×10^-5V + V = 3×10^8 - 20713.13
1.000069V = 299979286.9
V = 299979286.9/1.000069
V = 299,958589.8 m/s
Therefore, Rigel's velocity relative to us is 299,958589.8 m/s