Write the given expression as a single trigonometric function.
StartStartFraction tangent (StartFraction 3 pi Over 7 EndFraction) minus tangent (StartFraction 2 pi Over 5 EndFraction) OverOver 1 + tangent StartFraction 3 pi Over 7 EndFraction) tangent (StartFraction 2 pi Over 5 EndFraction) EndEndFraction