# Method of undetermined coefficent

1. May 13, 2005

### vabamyyr

method of undetermined coefficent is applied when g(x) is exponent, polynomial or trigonometric function. What will happen if g(x)= lnx or some other log function
ay + by`+ cy = g(x), where g(x)=log function. What method to use then?

2. May 13, 2005

### dextercioby

If "a","b","c" are constants wrt "x",then Lagrange's method cannot fail.The method of variation of constants.

Daniel.