余弦定理

This article takes the teaching of conic sections as an example. By designing worksheets, teachers can introduce the historical material about conic sections to students. By way of using Apollonius' definition of parabola, ellipse and hyperbola, teachers can introduce the geometric aspect of "conic section" to students. By using the concept of " latus rectum " in Conics , we can connect "conic sections"-- representation of geometrical aspect, with "the equation of conic sections"-- representation of algebraic aspect to improving insufficiency of text books.

同时本文也试著从历史文本中寻找材料，简单举例说明数学教师可以如何应用这些史料在几何单元教学上，例如三角函数的正余弦定理，最后再以圆锥曲线的正焦弦为例，说明如何利用数学史料於此单元的教学，尤其是阿波罗尼斯的《锥线论》中对圆锥曲线的3个命题，将此3个命题的内容与意涵，尤其是正焦弦在圆锥曲线的几何意义上所扮演的角色，将其适当地融入教学中，将可使学生真正学习圆锥曲线的几何知识，而不再只是代数形式的几何知识。

In this paper,the methods of distance geometry are used to explore the angles of a simplex ,and the second cosine law of a simplex in another form is obtained.

运用距离几何的研究方法，研究了和单形相关的角，给出了单形第二余弦定理的另一种形式，以此为基础得出了BartO¨s体积公式一种简洁的证法；探讨了单形的几个体积公式之间的联系，并推广了单形的一个体积公式。

After trying several different ways to find the map of contour lines, we use color segmentation to construct the map of contour lines, and use the law of cosine to estimate the length of contour line we sample. We also estimate the slope of contour lines and compute how they should extend in the inpainting domain.

所以我们提出一个用来修补卡通的新inpainting演算法，我们使用颜色分群的技术来取得结构性资料或称轮廓线并且使用余弦定理来计算轮廓线取样长度，以我们取样的轮廓线推算出在修补区域内轮廓线的结构性，进而使用类似於现实生活中的贝兹曲线来重建消失的结构性资料。

Then,the cosine value of central angle between the spacecraft and the descending node is solved by using cosine theorem of spherical geometry to avoid the cumbersome solving process by judging the flight direction of a satellite and the latitude of sub-satellite point in an original calculation model of image motion speeds.

通过球面几何的余弦定理直接求解航天器与降交点相对地心夹角的余弦值，避开了原像移速度计算模型中通过判断卫星飞行方向和星下点纬度来求解航天器与降交点相对地心夹角余弦值这一过程。

We would simply require them to recognize, appreciate, and memorize the great pieces of language of the past - literary equivalents of the Pythagorean Theorem and the Law of Cosines.

我们只会需要他们认识、欣赏、记住过去时代语言方面的伟大篇章——就好比是数学中毕达哥拉斯定理和余弦定理。

We would simply require them to recognize, appreciate, and memorize the great pieces of language of the past- literary equivalents of the Pythagorean Theorem and the Law of Cosines.

我们仅仅需要他们认识、赏、住历史上伟大的语言篇章——就好比是数学中毕达哥拉斯定理和余弦定理。

We wouldsimply require them to recognize, appreciate, and memorize thegreat pieces of language of the past - literary equivalents of thePythagorean Theorem and the Law of Cosines.

我们仅仅需要他们认识、欣赏、记住历史上伟大的语言篇章——就好比是数学中毕达哥拉斯定理和余弦定理。

The sine, law of cosines's several sine law and the law of cosines are three angular corner relations and three jiao functions plants using abstract the is most common, the most important two theorems.

正弦定理和余弦定理是三角形边角关系及三角函数种最常见、最重要的两个定理。

We would simply require them to recognize, appreciate, and memorize the great pieces of language of the past - literary equivalents of the Pythagorean Theorem and the Law of Cosines.

我们仅仅需要他们认识、欣赏、记住历史上伟大的语言篇章——就好比是数学中毕达哥拉斯定理和余弦定理。

The sine, law of cosines's several sine law and the law of cosines are three angular corner relations and three jiao functions plants using abstract the is most common, the most important two theorems.

帮我把这段文字翻译为英文，谢谢，非常感谢摘要正弦定理和余弦定理是三角形边角关系及三角函数种最常见、最重要的两个定理。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。