Answer: V = 4.35 × 10^12 m/s
Explanation: To calculate Rigel velocity relative to us, we should use doppler effect formula.
Fo = (c ) / ( c - Vs) × f
Fo/f = (c ) / ( c - Vs)
4.26 × 10^10 = (3×10^8) 6.17×10^14/(3×10^8 - V)
4.26×10^10/6.17×10^14 = (3×10^8)/(3×10^8 - V)
6.9×10^-5 = (3×10^8)/(3×10^8 - V)
Cross multiply
20713.13 - 6.9×10^-5V = 3×10^8
Collect the like terms
6.9×10^-5V = 3×10^8 - 20713.13
6.9×10^-5V = 299979286.9
V = 299979286.9/6.9×10^-5
V = 4.3475 × 10^12 m/s
Therefore, Rigel's velocity relative to us is 4.3475 × 10^12 m/s