Inequality formula is a formula with unequal ends, which is a mathematical term. The basic properties of common inequalities are: a >；; b，b & gtc→a & gt； c，a & gtb→a+c & gt； b+c，a & gtb，c & gt0→AC & gt； bc，a & gtb，cb & gt0，c & gtd & gt0→AC & gt； bd，a & gtb，ab & gt0→ 1/ab & gt； 0→a^n>； b^n。

In mathematics, vectors (also known as Euclidean vectors, geometric vectors and vectors) refer to quantities with magnitude and direction. It can be imagined as a line segment with an arrow.

The arrow indicates the direction of the vector; Line segment length: indicates the size of the vector. The quantity corresponding to a vector is called a quantity (called a scalar in physics), and a quantity (or scalar) has only a size and no direction.