Math Chapter Wise Ordinary And Partial Differential Equations, Integral Equations And Calculus Of Variations English MCQ UP PCS (Pre) 2009 Q.The orthogonal trajectories of y = mx, where m is a parameter, are Ax2 +2y2 = c2 Bx2 -y2 = c Cx2 +2x+y2 = c Dx2 +y2 = c2 Show answer Correct answer: x2 +y2 = c2