Page:Joseph Louis de Lagrange - Œuvres, Tome 6.djvu/82

et il n’y aura qu’à mettre, dans les expressions de $\mathrm {R_{1},Q_{1},P_{1}}$ de l’Article X, $\circledast$ au lieu de ${\mathfrak {S}}_{2},$ $\delta _{1}$ au lieu de $\Delta (r_{1},r_{2}),$ $\rho _{1}$ au lieu de $r_{2},$ $\psi$ au lieu de $\varphi _{2},$ et supposer $p_{2}=0.$ De cette manière on aura, en vertu de l’action du Soleil,

${\begin{aligned}\mathrm {R} _{1}=&\circledast \left[{\frac {r_{1}-\rho _{1}\cos(\psi -\varphi _{1})}{\delta _{1}^{3}}}+{\frac {\cos(\psi -\varphi _{1})}{\rho _{1}^{2}}}\right],\\\mathrm {Q} _{1}=&\circledast \left[{\frac {\rho _{1}\sin(\psi -\varphi _{1})}{\delta _{1}^{3}}}-{\frac {\sin(\psi -\varphi _{1})}{\rho _{1}^{2}}}\right],\\\mathrm {P} _{1}=&\circledast {\frac {r_{1}p_{1}}{\delta _{1}^{3}}}.\end{aligned}}$

XII.

Donc, en joignant ensemble les forces qui proviennent de l’action des trois satellites ${\mathfrak {S}}_{2},{\mathfrak {S}}_{3},{\mathfrak {S}}_{4},$ et du Soleil sur le satellite ${\mathfrak {S}}_{1}$ on aura les valeurs complètes de $\mathrm {R_{1},Q_{1},P_{1}} ,$ exprimées de la manière suivante

${\begin{aligned}\mathrm {R} _{1}&={\mathfrak {S}}_{2}\left[{\frac {r_{1}-r_{2}\cos(\varphi _{2}-\varphi _{1})}{\Delta (r_{1},r_{2})^{3}}}+{\frac {\cos(\varphi _{2}-\varphi _{1})}{r_{2}^{2}\left(1+p_{2}^{2}\right)^{\frac {3}{2}}}}\right]\\&+{\mathfrak {S}}_{3}\left[{\frac {r_{1}-r_{3}\cos(\varphi _{3}-\varphi _{1})}{\Delta (r_{1},r_{3})^{3}}}+{\frac {\cos(\varphi _{3}-\varphi _{1})}{r_{3}^{2}\left(1+p_{3}^{2}\right)^{\frac {3}{2}}}}\right]\\&+{\mathfrak {S}}_{4}\left[{\frac {r_{1}-r_{4}\cos(\varphi _{4}-\varphi _{1})}{\Delta (r_{1},r_{4})^{3}}}+{\frac {\cos(\varphi _{4}-\varphi _{1})}{r_{4}^{2}\left(1+p_{4}^{2}\right)^{\frac {3}{2}}}}\right]\\&+\circledast \ \ \left[{\frac {r_{1}-\rho _{1}\cos(\psi \ -\varphi _{1})}{\delta _{1}^{3}}}+{\frac {\cos(\ \psi \ -\varphi _{1})}{\rho _{1}^{2}}}\right],\\\\\mathrm {Q} _{1}&={\mathfrak {S}}_{2}\left[{\frac {r_{2}\sin(\varphi _{2}-\varphi _{1})}{\Delta (r_{1},r_{2})^{3}}}-{\frac {\sin(\varphi _{2}-\varphi _{1})}{r_{2}^{2}\left(1+p_{2}^{2}\right)^{\frac {3}{2}}}}\right]\\&+{\mathfrak {S}}_{3}\left[{\frac {r_{3}\sin(\varphi _{3}-\varphi _{1})}{\Delta (r_{1},r_{3})^{3}}}-{\frac {\sin(\varphi _{3}-\varphi _{1})}{r_{3}^{2}\left(1+p_{3}^{2}\right)^{\frac {3}{2}}}}\right]\\&+{\mathfrak {S}}_{4}\left[{\frac {r_{4}\sin(\varphi _{4}-\varphi _{1})}{\Delta (r_{1},r_{4})^{3}}}-{\frac {\sin(\varphi _{4}-\varphi _{1})}{r_{4}^{2}\left(1+p_{4}^{2}\right)^{\frac {3}{2}}}}\right]\\&+\circledast \ \ \left[{\frac {r_{4}\sin(\psi \ -\varphi _{1})}{\delta _{1}^{3}}}-{\frac {\sin(\ \psi \ -\varphi _{1})}{\rho _{1}^{2}}}\right],\end{aligned}}$