4. 2 +i 13. the complete integral of the partial differential equation-2 e* is 1. -x)+ xo2(y + x)+e*y 2. piy +x) +xp2(y +x) + xe*2 3. o(y-x) + o2(y +x) + e+2y 4

4. 2 +i 13. The complete integral of the partial differential equation-2 e* is 1. -x)+ xo2(y + x)+e*y 2. piy +x) +xp2(y +x) + xe*2 3. o(y-x) + o2(y +x) + e+2y 4.1y+ x) + xp2(y +x) +e**y