ドップラー効果波長正面計算機

I want to calculate Wavelength in Front of a Moving Source(λf)Wave Velocity(v)Source Velocity(us)Source Frequency(f0)
Wave Velocity(v) =	m/s
Source Velocity(us) =	m/s
Source Frequency(f0) =	Hz
Wavelength in Front of a Moving Source(λf) =	m