凡是学过微积分的人,都知道著名的微分中值定理:f(x)-f(x_0)=f′(x_0+θ(x-x_0))·(x-x_0).(0<θ<1)这个定理也叫做拉格朗日中值定理,以纪念最先给出这一结果的著名数学家拉格朗日。1736年1月25日,约瑟夫·路易士·拉格朗日诞生于意大利西部的都灵。他的家庭一度十分富有,但不幸由于父亲做生意赔钱而破产。少年时代的拉格朗日对于数学并 Everyone who has studied calculus knows the well-known differential mean value theorem: f(x)-f(x_0)=f’(x_0+θ(x-x_0))·(x-x_0).(0<θ <1) This theorem is also called the Lagrangian mean value theorem to commemorate the famous mathematician Lagrange who first gave this result. On January 25, 1736, Josef Louis Lagrange was born in Turin, western Italy. His family was once very rich, but unfortunately he went bankrupt because his father lost money doing business. Lagrange in childhood and for mathematics