数学方法（Mathematical method）.doc

数学方法（Mathematical method） It is important to preserve the limit, that is, within a certain interval, the function is in accord with the limit 1, the limit is divided into the general limit, and there is a series of limits (difference in the limit of the sequence of divergence, is one of the general limit) 2, the solution to the limit is as follows: (I can list all out!!!!! Can you add anything? The transformation of 1 equivalent infinitesimal, (only in time, but not necessarily in the multiplication and addition and subtraction may be used but the premise is must prove that the split limit still exists) X e -1 (1+x) or a -1 is equivalent to Ax etc.. Memorize all (when x approaches infinity, it is reduced to infinitesimal) 2 strokes he rules (big topic sometimes suggest you use this method) First of all, his use has strict premises!!!!!! It must be X approach, not N approach!!!!!!! (so when facing the limit of a series, we must first translate into the limit of the X approach, of course, the N approach is a case of the X approach, and it is a necessary condition (and the n of the limit of the series, of course, is the infinity of Yu Zheng The derivative of the function must be present!!!!!!!! (if you tell g (x), did not tell you whether you can directly guide, undoubtedly killed!!) Must be 0 to 0, infinitely greater than infinity!!!!!!!!! Of course, we should also note that the denominator can not be 0 He put pen to paper is divided into 3 situations in law 10 to 0, infinitely more than ever 20 multiplied by infinity, minus infinity (as infinity is greater than infinitesimal), so infinity is written as an infinitesimal reciprocal form. After the entry, this will become a form of 1 30 of the 0, 1 of the infinite, 0 times of infinity For (index exponential equation method is the main method) from the index also log, so that the function of power on the move down, is written in 0 and infinite form, (this is why, only 3 kinds of LNx both tend to infinity when his power m