hi all,

im practising separation of variables for partial differential equations. i came across this site which says:

2. Separation of Variables

differential equations.''NOTE:In this variables separable section we only deal withfirst order, first degree

so , if i have a second order or above PDE, then i cant use separation of variables?

i thought one can use separation of variables for example in the wave equation!! that is a second order PDE....

ok im confused

can anyone help me out?

i hope i am clear with this question problem

thank you all very much