In mathematics, the irrational numbers are all the real numbers which are not rational numbers, the latter being the numbers constructed from ratios (or fractions) of integers. When the ratio of lengths of two line segments is an irrational number, the line segments are also described as being incommensurable, meaning that they share no “measure” in common, that is, there is no length (“the measure”), no matter how short, that could be used to express the lengths of both of the two given segments as integer multiples of itself.

Elementary function

极限 体现了函数的变化趋势， 存在与否， 与函数在点a处的取值无关， 即使函数在该店无定义， 极限也可能存在

有界量

等价无穷小

无穷小和无穷大关系

反三角函数

罗尔定理 - 公众号高数叔

导数在研究函数中的应用 高中数学选修2-2

平均速度， 瞬时速度(instantaneous velocity)

极限

###切线（tangent line）

高中数学 信息技术公式

Where Is Times Go ?

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