Math Chapter Wise Limit, Continuity And Differentiability Of Function Of Two Variables And Partial Differentiation English MCQ UPPSC Polytechnic Lecturer 2021 (I) Q.If 2 xy z = e,x = tcost,y = tsint, then the value of dz π at,t = is - dt 2 A2 4 π B2 – 8 π C3 – 8 π D3 8 π Show answer Correct answer: 3 – 8 π