unsolvability

This introduced the idea of relative computability, or relative unsolvability, which opened up a new field of enquiry in mathematical logic.

这就引入了“相对可计算性”的观点，或者说相对不可计算性，于是开创了一个数理逻辑的新领域。

The unsolvability of implicit equations existing in the inversion algorithm in the inverse system method ( ISM) is considered, and a constructive inversion algorithm is presented for general nonlinear systems so as to avoid solving implicit equations via elimination method.

针对由于逆系统方法之求逆算法中求解隐函数方程的困难，通过消元法避开对隐函数方法的求解，提出了一般非线性多变量系统的构造性求逆算法。

This paper discusses the drawing of hyperbola normal through a point outside the hyperbola and points out the unsolvability of geometric drawing method and the unintegrality of optimization method.

对过双曲线外一定点的法线作图问题作了探讨，提出了几何作图法的不可解性及优化法解的不全性。

So far as present cryptanalytic methods are concerned, the cipher systems derived from some of these machines are very close to practical unsolvability.

以目前的密码技术来看，这些机器的性能是手工操作完全无法达到的。

Quantitative Analysis and Online Recovering Control of Power Flow Unsolvability

电力系统潮流计算不收敛的机理分析及其在线恢复控制