Synodic Period Formula

Equation for calculate synodic period is,

$$\frac{1}{P_{\mathrm{syn}}}=\frac{1}{P_1}-\frac{1}{P_2}$$

where,
P₁ = sidereal period of 1st body around the 3rd (P1 < P2)
P₂ = sidereal period of 2nd body around the 3rd (P1 < P2)
P_syn = synodic period