Talk:Differential algebra

From Wikipedia, the free encyclopedia

Mathematics Portal This article is within the scope of WikiProject Mathematics, which collaborates on articles related to mathematics.
Mathematics rating:	Start Class	High Priority	Field: Algebra
Please update this rating as the article progresses, or if the rating is inaccurate. Click to show/hide comments. Please add to or update the comments to suggest improvements to the article. Geometry guy 21:55, 3 June 2007 (UTC)

[edit] elementary Leibniz differentials

I look in vain in wikipedia for an elementary explanation of the differential, (not the derivative). The Leibniz notations, and assumes dx and dy. Formal differentiation can be defined: if x is a variable then so is dx, if x is constant then dx = 0, if x is an independent variable then dx is constant and d²x = 0, the sum rule d(x+y) = dx+dy, and the product rule d(x·y) = dx·y+x·dy. This is sufficient to deduce differentiation of formal power series. Differentiation of an algebraic equation (such as x²+y² = r²) gives a differential equation (such as x·dx + y·dy = 0). Perhaps this is what this technical article on differential algebra is about ? Bo Jacoby 08:06, 7 August 2007 (UTC).