难解

However, to many subproblems, it is difficult or even possible to find exact solution.

然而， 精确求解子问题的解是非常难甚至是不可能。

Because the battery energy function has the exponential form, it is difficult to derive an analytic solution.

由于能量函数具有指数形式，很难获得解析解最小化能耗函数。

It is impossible for him to solve this maths problem. It is pretty easy for me to get a good job. It is said that our school will hold a sports meeting next month.

处理这件事情是很难的。2、你开车这么快是很危险的。3、他解出这道数学题是不可能的。4、我要找一份好的工作，这将会相当的容易。

Classic technique is the Newton-Raphson iterative. But when the system grows much bigger, the computing is much more hugeness. And it is very difficult to get the result in a short time under the current hardware and software situation.

经典的潮流计算方法是采用牛顿拉夫逊法迭代计算，但是随着电力系统的规模的增大，计算量异常庞大，在现有的软硬件的很难在短时间内得到潮流计算的解。

Hydrogenation of N=O group is easier than hydrogenolysis of the C-Cl bond on the hydrogenation of chloronitrobenzene .

氯代硝基苯中N=O极性键的加氢较C-Cl键的氢解容易进行，肉桂醛中C=O极性键较C=C键的加氢难。

It was well known that this metal would withstand the high heat required for incandescence over a long period without disintegration, but it was also known that tungsten was one of the most recalcitrant of the metals

人们熟知这种金属能长时间承受白炽所需要的高温而不会熔解，但人们也知道钨是金属中最难对付的。

Jaundiced by years of blue screens and having to kluge together their own "solutions," buyers have discovered the hard way that the best technology doesn't always carry the day, that pioneers don't always make the best providers, and that "second to market" is often a strategic advantage rather than a badge of disgrace.

蓝色屏幕、黄疸多年不用自己克鲁一起"解"难买主发现，最好的技术途径并不总是带有一天这并不总是尽开拓者供应而"第二市场"的战略优势，而不是常常挂着一个耻辱。

The entropy is a very important concept in physics, mathematics and system science. The problem of its minimum value under the condition of constraint is NP-complete and can't be analytical solved.

熵是物理学、数学、系统学等学科中一个非常重要的概念，在约束条件下熵的最小值问题属于NP难的组合优化问题，一般无法得到此问题的解析解。

The standard solubility product and solubility of compound salt ammonium molybdate· molybdenum trioxide at 0~100 ℃ condition are studied.

研究了难溶复盐钼酸铵氧化钼的标准溶度积常数和不同温度下的溶解度，测定了同离子效应对溶解度的影响，并用红外光谱分析了其解离形式。

The algorithms based on two necessary condition is monotone decreasing, for multi-extreme point in solution space, the distribution of final codebook seriously depend on that of initial codebook, it is difficult to cast off if get in local optimality.

然而这些算法本身属单调梯度下降算法，在解空间存在多极值点时，最终码书的分布较大依赖初始码书分布，一旦落入局部最优区域，很难摆脱。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。