题目

贷款买房是当今中国社会的一个热点话题，其实真正的贷款买房还包含着很多的学问。但这些学问的核心还是一个数学领域的优化问题模型。而本文正是试图通过数学手段研究此问题，得出一个优化组合。为千千万万的购房者提出一点儿建议。
本文主要采用了曲线拟合的方法来大致估算了教师的个人收入。利用残差最小原理和最小二乘法的方法拟合出了老师们的工资收入函数表达式。并对一个年轻教师未来若干年内的收入增长和职称提升作出了预测。同时，通过数列的知识和差分方程的原理，得出了两种不同的还贷方式的解析表达式。通过代值检验得出了两种方式各自所需要的条件，也从实践中明白了等额本息付款的还贷方式为什么会成为现在的购房主流。
由于本文作者功力欠深厚和时间关系等诸多原因，本文定有不少瑕疵。例如：在曲线拟合时的点略有偏少，这对拟合的效果产生一定影响。在贷款购房与还贷的那个阶段，实在是由于教师家庭至少是两个人的家庭，另一半的收入不好妄加猜测，所以也只能作简化处理。也请大家多多包涵。
最后，本文的诸多不妥之处还请各位老师，各位同学不吝赐教。

提问时间：2021-04-01

答案

Loan China today is a hot topic of society,when the true loan to buy a house also contains a lot of knowledge.But these knowledge core or a mathematics model of optimization problems.But this article is trying to studying the problem by mathematical method,get an optimal combination.For millions of homeowners put forward a little advice.
This paper mainly adopts curve fitting method to roughly estimate the teacher of personal income.Use residual minimum principle and least-square method fitting out teachers function expressions of wage income.And a young teacher next several years income growth and titles made a forecast.Ascending Meanwhile,through the series of knowledge and the principle of differential equation,it is concluded that the two different ways to engage the analytical expressions.Through the generation of value is obtained two ways to test their required conditions,also from practice for payment of the principal and understand why will become payments way now purchase of the mainstream.
Because the author capability owe deep and time relationship,and many other reasons,this paper will have many defects.For example:in the curve fitting point of microroughness for scarce,and somewhat fitting effect has certain influence.In a loan to buy houses the stage with borrowed,really was because the teacher family is at least two individual's family,and the other half income bad,so also can only guess hazard for simplified treatment.Also please bear with me a lot.
Finally,this paper many deficiencies still attention,teachers:please comment,the classmate.