Recent content by Mark_Twain_MO

Sorry, I meant: \partial/\partialx[K(x,u)\partialu/\partialx] I understand that \partial/\partialx[K(x)\partialu/\partialx] is a linear operator, but I do not get why making K a function of both x and u should non-linearize this operator.

Hello, Could anyone help explain why \partial/\partialx[K(x,u)\partialu/\partialu] is not a linear operator?