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Can anyone help me? I want to make the orbit ellipse. Please help me to fix my code. lagrangian = 1/2 (x'[t]^2 + y'[t]^2) + 1/Sqrt[x[t]^2 + y[t]^2]; eq = Table[ D[lagrangian, x1] - D[D[lagrangian, D[x1, t]], t] == 0,...